MAGAZINE NO. 1 – AUTUMN 2020
Feeding of aquarium fish Zoanthus corals in the marine aquarium Secrets of snakes
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Dear Readers, I am pleased to present the first issue of Tropical Edu Magazine. Once a quarter, recognized experts will share with you their reliable aquarium and terrarium knowledge. And if some of you wonder why so rarely, don’t worry, Tropical Edu Magazine is one of three segments of a rich educational platform prepared by Tropical, which you can use every day. It includes a magazine, blog and YouTube channel. Check www.tropicaledu.com for a blog where new entries are posted regularly. Every day, you can reach for interesting materials on freshwater and marine aquarium as well as terrarium. Comment and write to Tropical experts who will be happy to answer your questions. Videos published on YouTube are an attractive addition to the blog and the magazine. Visit Tropical Edu channel to find condensed knowledge and interesting shots from fish and reptile life. If you want to stay up to date, feel free to subscribe. The Tropical Edu platform is a reliable and proven source of knowledge. Our goal is to promote aquaristics and terraristics and support the development of hobbyists. Okay, now you should have a brief idea about the Tropical Edu project. But what can you expect in the first issue of TEM? Three knowledgeable articles, each from a different field. Bartek Stańczyk will tell you some interesting facts about Zoanthus corals, commonly known as Zoas. In my article ”Feeding of aquarium fish” you will find information about the nutritional value of invertebrates, immunoactive substances and herbs. Dawid Krótki will introduce you to the mysterious world of snakes. But that’s not all. How do you feel about biotope aquaristics? This is a new trend. Difficult and demanding, yet extremely engaging in various fields of science. Kamil Hazy, the leading propagator of biotope aquaristics in Poland, will explain what a biotope and biocenosis are and how not to get lost in all this. Pond owners will find tips how to prepare the pond for winter. The icing on the cake is an interview by Paweł Czapczyk with Krzysztof Kelman – the director of the Municipal Zoological Garden in Płock, a great expert and fan of live-bearing and egg-bearing fish. I wish you a pleasant reading and encourage you to benefit from the whole Tropical Edu platform content. Aleksandra Kwaśniak-Płacheta Chief editor
Chief editor: Aleksandra Kwaśniak–Płacheta, PhD Leading editor: Paweł Czapczyk, PhD DTP: Marek Kantor Publisher: Tropical Tadeusz Ogrodnik Cover photo: Paweł Czapczyk – Cichla temensis
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Tropical EDU Magazine
CONTENTS – TROPICAL EDU MAGAZINE NO. 1 Heart for aquaristics – Krzysztof Kelman interviewed by Paweł Czapczyk
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Feeding of aquarium fish – Aleksandra Kwaśniak-Płacheta, PhD 16 Zoanthids in the marine aquarium – Bartłomiej Stańczyk 28 Introduction to biotope aquarium – Kamil Hazy 38 Snakes – sacred and cursed creatures – Dawid Krótki 46 Autumn in the pond 56
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HEART FOR AQUARIS Krzysztof KELMAN interviewed by Paweł Czapczyk
Paweł Czapczyk, PhD For nearly 40 years a passionate aquarium and terrarium hobbyist, writer, editor and breeder; organizer of exhibitions and conferences on aquarium and terrarium hobby; author of many books and press articles, as well as radio broadcasts and screenplays for documentary films; nature photographer, editor-in-chief of “Aquarium Magazine”.
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Tropical EDU Magazine
STICS
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Heart for aquaristics
Krzysztof Kelman The director of the Municipal Zoological Garden in Płock, president of the Poecilia Reticulata Club, an active member of Goodeid Working Group and, above all, a legend of Polish and international aquaristics, interviewed by Paweł Czapczyk.
Paweł Czapczyk: When did your adventure with aquaristics begin? Krzysztof Kelman: Exactly 51 years ago. I was 9 years old when I got my first aquarium, a 80-litre framed tank, as a Christmas present. At that time it was considered very big. It was put on a special stand and decorated even before Christmas. On Christmas Eve 1969, I went with my dad to buy my first fish. I remember it as if it was today. I got two zebrafish, three spot gourami, two guppies and two swordtails. And at the bottom of the stand there was an additional shelf. After a few months I had a second tank standing there, this time a 60-litre one. If you were to compare the approach to our hobby a few decades ago to the current one, what would you pay attention to in the first place?
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In the past almost every young boy went through the ”aquarium stage”. Almost all my colleagues who saw my tank had their own within a year. In every backyard, in every block there was somebody breeding fish and bringing a lot of joy to everyone around. And today, kids and teenagers have fish... in their computers. And yet, in order to catch the bug and become an aquarium hobbyist for life, you have to pass the aquarium hobbying stage in your teenage years. Do you have similar observations as a director of the Płock zoo? My experiences with the zoo are indeed similar. In the 80s and early 90s we were visited by enthusiasts who wanted to talk, exchange experiences or fish. And it’s been a long time since I’ve seen an amateur aquarium hobbyist come to the zoo
Tropical EDU Magazine
The interior of the Aquarium pavilion
for this purpose only. In the past, aquarists put more heart into their hobby. They were more committed and had to show more initiative to learn something and get the desired heater or pump. Today, all good quality equipment is at your fingertips, and people often want to buy a ready-made aquarium and make it look like a picture on the wall. I can see that you have a genuine passion for aquaristics. By the way, you once mentioned to me about your secret farming of seasonal fish in the dorm. Could you tell the story to the readers of Tropical Edu Magazine? Actually it was not secret, because the managers of PĹ‚ock and Bydgoszcz dormitories did not object. And in the 80s Austrolebias, Nothobranchius and some species of Aphyosemion were very rare in
Poland. And I’ve been reproducing them in the dorm, sometimes on a large scale. And their impressive spawning, burying in the peat or beautifully colored males chasing females attracted crowds of the students, sometimes even half of res-
Myripristis murdjan preys mostly at night
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A fragment of the exhibition – on the left ”Coral Reef”
idents of the dorm. I myself tried to fuel their interest by flooding peat with water and demonstrating how young fish hatch after an hour. But your beloved fish have always been, and still are, live-bearing fish. I’m thinking here of both wild fish, as well as the breeding forms of one species – guppy. Yes, the guppy is the passion of my life. Already as a teenager I watched the Poecilia Reticulata Club with admiration, and considered their famous members an upper class. And it happened that a few years ago, I became a head of this club. But I also have a great love for wild live bearers, as I have bred more than 90 rare and hardly obtainable species. Working in the zoo and being a member of the unfortunately no longer existing Czech club
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of wildlife live-bearing fish gave a lot of opportunities for exchange with breeders from all over the world. But we keep talking about freshwater fish. Because I’m passionate about freshwater aquaristics. I think that Poland is not financially ready for a genuine marine aquaristics. For instance, I have managed to start the largest 40,000 litres aquarium in the zoo with blacktip sharks while my colleagues in the western countries have 5,000,000 or 8,000,000 litres of aquariums. That shows differences in our budgets. And what else – apart from sharks – is worth paying attention to when you visit aquarium pavilion in the Płock zoo?
Tropical EDU Magazine
A reservoir with small species of native ichthyofauna (inside)
We have created cross-sectional exhibitions of fish from all over the world – from freshwater to marine. We show the classic
environment of the Amazon with the two-metre-long arapaimas, which came to us from Peru a dozen or so years ago, and with
The Parkinson’s rainbowfish (Melanotaenia parkinsoni) from Antipodes
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The Pumpkinseed (Lepomis gibbosus) is a representative of North American waters
piranhas, which today almost everyone can keep in an aquarium. We have the biotopes of Lake Malawi and Tanganyika and the environment of Australia and Asia. We also show water habitats of North America, not often seen in zoos. We are exceptional-
ly proud of our Mississippi paddlefish. They are difficult to keep, not so much because of the cooled water, but because of their feeding patterns. Like some whales, they filter the water, catching the tiny food floating in it. For some time now, we have also
The Blacktip shark (Carcharhinus limbatus)
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Tropical EDU Magazine
The American Paddlefish (Polyodon spathula) from the Mississippi basin can be 2 m long
been building a coral reef in a large 12-metre long tank. Visitors are also interested in your cold water aquariums with domestic ichthyofauna.
We have several tanks with Polish species, which are not at all easy to maintain. Swamp minnow is one of our top specimens. A truly unique species, which is close to extinction and therefore protected by a special nature rescue program. At the
A shoal of red-bellied piranhas (Pygocentrus nattereri) from the Amazon www.tropicaledu.com
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zoo, we breed minnows in a specially prepared pond but we also exhibit them in an aquarium set up next to the pond, in the open air. Is it the mission of modern zoos to breed the endangered species and introduce them back into their environment? Yes. It’s about breeding of rare and endangered species, or even those that are already extinct in nature and have remained only in zoos. The end result is reintroducing
Seahorses always attract visitors’ attention
Why? Because in Płock we are carrying out a program protecting our Polish species, and not – as in many other entities – exotic
The Giant gurami (Osphronemus goramy) is an edible fish in Asia
animals to the wild. Programs including domestic species are particularly valuable. I personally joined the project of Professor Jacek Wolnicki from the Institute of Inland Fisheries in Olsztyn, which monitors all swamp minnow stations in Poland, breeds the fish and reintroduce them to specific reservoirs. We want to reproduce it in Płock in such a quantity to be able to strengthen the populations living in the wild and release them to the deserted habitats where they historically lived. And last year at the convention of EAZA (European Association
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of Zoos and Aquaria), the organization that brings together the most important zoos of the Old Continent, I presented a special poster about the protection, breeding and reintroduction of swamp minnows, which received a very positive response from all directors of European zoos.
ones. This aroused enthusiasm, which we tried to use to promote the idea throughout all Europe. And could you briefly address the issue of feeding aquarium fish? All aquarists, even those who are not very advanced, know well the importance of feeding and proper diet. Apart from maintaining the right water parameters, the right tank size or reasonable prevention, feeding is simply one of the pillars of aquaristics. In the old days, feeding took place
Tropical EDU Magazine
in a way that was natural: we caught live food animals and plankton in the ponds. We would bring them home in buckets, then sort everything, sift and finally feed them to our fish. We also had dried daphnia and chicken egg yolk at our disposal. Currently, aquaristics is based on a whole range of foods produced for hobbyists by specialized companies. We have everything we might need: foods of every possible granulation, flakes of various compositions, special foods for specific
Top quality foods for live-bearing fish
The Boeseman’s rainbowfish (Melanotaenia boesemani) appeared in aquarium breeding in the 1980s
families, types or even species of fish, and finally, foods that stimulate coloration, strengthen the body and support the immune or digestive system... Just remember not to feed your fish with the cheapest food available because their composition will always be poor.
AMERICA, GUPPY and SUPER SPIRULINA FORTE are a perfect food set for small live-bearing fish. Regularly administered, they ensure intensive colors, greater resistance to pathogens and proper digestion.
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The Grayling (Thymallus thymallus) lives mostly in mountain rivers
Do you use Tropical foods in the Płock zoo? Yes, I must say we’ve been using Tropical foods in the Płock zoo for years. And not only because these are the best Polish foods (no other Polish company is able to match Tropical’s quality). Products of this brand are at least as good as western, German foods, but several times cheaper. Their advantages include availability on the market, relatively low price and, above all, excellent quality and diversity of the offer. I can sincerely recommend them to any aquarium hobbyist. As a president of the Poecilia Reticulata Club, you are organising the European Guppy Championship. This year, however, your ambitious plans have been thwarted by the Covid-19 pandemic. In that case, when can we expect the next championship event in Płock? The year 2020 for both national and international competitions and exhibitions turned out to be completely lost – in-
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cluding the World Cup which were supposed to be held in China, as well as the classification in the Polish Championship. In Płock – in accordance with the IKGH regulation – we were to organize this year’s European Guppy Championships in the category of pairs and we have already received an assurance from the president of the IKGH that all key events of this year will be moved to 2021, according to the calendar. So I invite you to Płock for the first weekend of September next year.
Photos by Paweł Czapczyk
Tropical EDU Magazine
FOOD FOR FISH AND FRY with probiotic
Tiny granules
0.5 mm
Probiotic added to the foods contains viable Bacillus subtilis endospores, which stabilize gut microflora, facilitating utilization of nutrients, and this in turn reduces contamination of water with fish’s feces. The synergic effect of probiotic, beta-glucan, vitamins and carotenoids significantly improves overall condition and immune system of fish and fry. Pro Defence micro size fry food contains as much as 60% protein.
BENEFITS FOR FISH FROM THE USE OF FOODS WITH PROBIOTIC increased resistance to pathogens
faster growth and greater fertility
stronger and bigger offspring
better utilization of food
better survival rate of the fry
increased resistance to stress
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FEEDING OF AQUARIUM FISH
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Aquarium fish feeding Aleksandra Kwaśniak-Płacheta, PhD Hydrobiologist, expert on feeding and breeding of ornamental fish, aquarium enthusiast. A highly recognized speaker of many aquarium training courses and symposiums. Author of articles published in domestic and foreign magazines including ”Nasze Akwarium”, ”Magazyn Akwarium”, ”Planeta Zwierząt”, ”Tanganika”, ”Fauna & Flora”, ”Pet Market”, ”Aquafeed Magazine”, ”Pet Worldwide” and various publications of Wrocław Aquarium Association.
Aquarium fish hobbyists can enjoy an
bility varies depending on the season. In
impressive range of species, whose
the absence of their primary food, fish are
number is increasing every year. In re-
forced to resort to less palatable alterna-
sponse to the growing aquarists’ needs
tives, which they have declined so far. It’s
manufacturers introduce foods with
not possible to imitate natural living con-
more and more sophisticated formulas.
ditions of wild fish but you can compose
However, data concerning dietary hab-
a diet based on products with nutri-
its of wild specimens are rudimentary
ent-rich compositions to diversify their
and extremely hard to obtain. The know-
diet, hence prevent nutritional deficien-
ledge about fish’s needs comes from ob-
cies and numerous medical disorders.
servation rather than rigorous research.
The most vulnerable is the hatch. Here
The common practice is to use research
any deficiencies can lead to deformities
carried out on fish for human consump-
and developmental disorders. For in-
tion However, it is not possible to create
stance, Artemia nauplii, commonly used
and maintain natural network of feed-
for rearing fry, lead to the decalcification
ing relations in aquarium and many spe-
of bones and reduction of the survival
cies-typical behavior patterns are sim-
rate, if not supplemented by other foods.
ply not observed. No wonder that a diet of aquarium fish is becoming more uni-
FISH’S NUTRITIONAL PREFERENCES
versal.
In terms of their nutritional requirements ornamental fish can be divided into her-
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In the wild fish feed on insects, molluscs,
bivores, omnivores and carnivores. For-
crustaceans, fish, plants, algae, etc. These
mulated foods for herbivorous fish should
foods differ in terms of quality and quan-
be characterized with high content of
tity of nutrients. In addition, fish’s diets
plant material, including spirulina, chlo-
vary throughout the year, as food availa-
rella, Kelp algae, spinach, nettle, etc. They
Tropical EDU Magazine
HERBIVOROUS FISH
CARNIVOROUS FISH
OMNIVOROUS FISH
10%
15% 30%
20%
25%
70%
70%
60%
vegetable foods
high-protein foods
multi-ingredient foods
multi-ingredient foods
vegetable foods or animal foods rich in chitin
vegetable foods high-protein foods
high-protein foods
should also be fed with fresh or frozen
products enriched with various natural re-
plants, mostly spinach, broccoli, zucchini,
sources that improve fish’s health, enhance
carrots, etc. For carnivorous fish, which in
their coloration and increase their resist-
the wild feed on fish, roe, fry and inver-
ance to diseases.
tebrates, there’s a choice of frozen foods
The diversity of formulas is accompanied
(krill, shrimps, fish fillets, squid, Daphnia
by a variety of forms in which formulated
pulex, Artemia, bloodworms, Tubifex etc.)
foods are available, so you can choose prod-
and live foods (fish, Daphnia, Artemia,
uct perfectly adjusted to the size of your
bloodworms, Tubifex, glassworm etc.) and
fish’s mouth and their way of feeding (from
multi-ingredient and high-protein formu-
the surface of the water, its middle layers or
lated foods.
from the bottom). The best feeding solution for bottom-feeders are granules and tab-
FORMULATED FOODS
lets. Fish feeding in the middle layers of the
FOR AQUARIUM FISH
tank or at the bottom prefer slowly sinking
Formulated ready-made foods available on
granules, which turn out particularly effec-
pet market can be divided into: multi-in-
tive in multi-species tanks with fish eating
gredient universal foods (used in feeding
in various parts of the aquarium. Fish with
of most popular aquarium fish species)
small mouth eating under the surface of
and specialist foods, dedicated to particular
water will choose flakes, which prove highly
species or groups of fish with sophisticated
effective in tanks where intraspecific com-
dietary demands, such as Tropheus cich-
petition takes place and where weaker fish
lids, Malawi cichlids of mbuna group (which
have a limited access to food. Flakes, float-
feed on periphyton), breeding discus, gold-
ing all over the tank, are easily accessible
fish, red parrots or algae-eaters from Lori-
even for smaller and weaker fish. Tablets
cariidae family. A special group of foods are
are recommended for timid fish, as they
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PLACEMENT OF THE MOUTH
ZONE OF FEEDING
upper
surface of the water
FORM OF THE FOOD
flakes pellets sticks dried and freeze-dried foods
medium
middle layers of water
granules chips flakes adhesive tablets plano-convex tablets
lower
bottom of the tank
adhesive tablets sinking tablets plano-convex tablets wafers granules flakes
can be placed in fish’s favourite hiding plac-
immune system, e.g. stabilised vitamin C,
es and for feeding the fry due to their small
beta-glucan, unsaturated fatty acids, spi-
particles.
rulina, Kelp algae, chlorella, etc. Stabilised vitamin C is a L-ascobyl-2-poly-
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IMMUNITY ENHANCING COMPONENTS
phosphate resistant to high temperatures.
OF FORMULATED FOODS
Vitamin C reduces stress, stimulates the
Prevention in fish is more effective than
immune system, strengthens blood ves-
medical treatment. Well-nourished fish
sel’s walls and accelerates wound healing.
with a strong natural resistance to diseas-
Unsaturated fatty acids (UFAs), including
es is more likely to cope with stress (trans-
long-chain fatty acids Omega-3 and Ome-
port from farms to wholesalers, store,
ga-6, accelerate the regeneration of tis-
the customer’s home) and pathogens. In
sues, including skin, improving its function
ready-made foods for ornamental fish one
as a protective barrier. Moreover, they are
can find numerous substances and re-
a building material of hormone-like cellular
sources, whose components enhance fish’s
messengers ‒ prostaglandins and repro-
Tropical EDU Magazine
ductive cells. Part of the demand for Omega-3 and Omega-6 fish cover themselves by producing them from simple UFAs, which they obtain from food. However, carnivorous and marine fish should be supplied with Omega-3 fatty acids, because their ability to process them from simple UFAs is small. Beta-1.3/1.6-Glucan ‒ a polysaccharide derived from yeast’s cell walls ‒ is a natural immune stimulator that directly affects macrophages, increasing their capacity for phagocytosis of alien cells and their own
the dry matter) and richness of essential
cancer cells.
amino acids. Health benefits are attributed
Extremely valuable components of foods
to Chlorella Growth Factor, rich in nucleic
for aquarium fish are algae and spirulina
acids. Kelp algae is a mixture of marine sea-
(Arthrospira platensis). The share of the
weed belonging to the brown algae, which
latter in fish feed depends on, inter alia,
are rich in minerals, including well-as-
a very high protein content (55-70%) char-
similable
acterized by a high digestibility (90%). In
iodine compounds,
addition, protein of spirulina contains most
UFAs, and vitamins.
essential amino acids for fish (if not all). The
Their addition has
cell’s walls of this cyanobacterium are com-
a beneficial effect
posed of mucopolysaccharides, which act
on metabolism and
as immunostimulators. In the cells of spi-
general
rulina one should find 3 times more chlo-
of the fish.
organic
condition
rophyll than in plants. Chlorophyll reduces the number of putrefactive bacteria in the
HERBS IN THE
gastrointestinal tract. The high content
AQUARIUM
of carotenoids, especially beta-carotene,
Not only have the
makes foods with spirulina intensify colora-
herbs been applied
tion in fish, which is essential in case of col-
to treat people, they are also commonly
ourful breeding forms. Thanks to so many
used as a dietary supplement in feeds for
different substances spirulina enhances vi-
livestock and domestic pets. Herbs en-
tality and encourages the immune system.
hance food palatability, stimulate animal’s
Other relatively common algae supple-
appetite, aid digestion and improve overall
ments of aquafeed are chlorella and Kelp
health. They also act as an anti-inflammato-
algae. Chlorella is known for its high con-
ry, antidiarrheal and bacteriostatic agents.
centration of chlorophyll (7% in the dry
Herbs are also present in the aquarium.
matter) and large protein content (50% in
They play an important role in the prepara-
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tion of water and are used as a component
it had been added by fish enthusiasts to
of both formulated foods and those pro-
mixtures they had prepared in their homes,
duced in house conditions. In Europe there
especially the ones for the discus, often tar-
are 25 species of basic herbal raw materials,
geted by gastrointestinal parasites.
including garlic and common nettle, which
Foods for ornamental fish also utilize nettle
are used in foods for ornamental fish. To
(Urtica dioica). The active substances in this
manufacture prepared food producers also
plant are organic acids, flavonoids, carote-
use plants rich in the so called fitamins,
noids, tannins, and others. Thanks to them
which act on the body in a manner similar
nettle regulates digestion. As a food sup-
to vitamins. But unlike the vitamins, they do
plement it has a beneficial influence on di-
not have to be delivered each day. Fitamins
gestion and provides a number of fitamins,
are present in vegetable and herbal plants.
vitamins and trace elements.
They regulate metabolic processes, detox-
icate body and enhance overall condition.
INVERTEBRATES USED IN FEEDING
Fitamins include among others: polyphe-
OF ORNAMENTAL FISH
nols (flavonoids and phenolic acids), sulfur
Before fish enthusiasts could take ad-
compounds (such as allin in garlic), tannins
vantage of convenient and easy-to-store
and carotenoids. The exceptional sources of
formulated foods, they had had to use
fitamins in foods for fish are garlic, spinach,
natural foods, which they fished or bred
spirulina and Kelp algae.
themselves. Despite many advantages
Garlic (Allium sativum) is a well-known
feeding fish with living organisms has
spice and herbal plant. Its cloves are com-
one fundamental flaw – the organisms
posed of sulphur-containing compounds
derived from nature can be a source of
including allin which becomes allicin when
dangerous pathogens. To avoid this threat
garlic is crushed. This is allicin to which gar-
you can chose frozen, dried and freeze-
lic owes its strong antiseptic properties and
dried products. Invertebrates have also
its characteristic flavour. Garlic also contains
become the essential ingredient of for-
flavonoids, pectins, mucilages, several vita-
mulated foods.
mins and trace elements. Before it started
Antarctic Krill (Euphausia superba) is
to be widely used in ready foods for fish,
a source of easily-digestible protein, rich
Tropical EDU Magazine
in essential amino acids. It is readily con-
it is a perfect food for spawners and fish
sumed by fish, especially in its processed
weakened by illness or long transport,
form ‒ as an additive in flakes, granules
especially that fish take it very eagerly.
and tablets. It is also characterized by
Tubifex (Tubifex tubifex) lives in bottom
a high palatability, resulting from the
sediments, where they feed on organ-
presence of amino acids (glycine, proline),
ic matter, algae and bacteria that live in
nucleic acids and TMAO (trimethylamine
them. These organisms are very resistant
oxide). These substances affect the taste
to various pollutants that can accumulate
and smell of the food. This is of particu-
in them. However, using Tubifex from pol-
lar importance in case of feeding wild
luted environment can lead to poisoning
caught specimens and commercial farm-
of fish. Tubifex and chironomids are both
ing fish, which aren’t used to eat ready-
added to formulated, but subjected to
-made foods and need encouragement.
freeze-drying process first.
Apart from valuable protein Krill provides
Daphnia is a source of protein and fat
fish with unsaturated fatty acids, out of
(including UFAs). It also contains a small
which 40% are PUFAs (polyunsaturated
amount of highly unsaturated fatty ac-
fatty acids), including 14.7% EPA and 8.3%
ids: EPA and DHA. Protein content (20-
DHA. Krill is also a great source of carot-
-25%) and fat content (2.4-20%) vary wide-
enoids ‒ natural pigments that enhance
ly depending on the feed base of the tank,
fish’s coloration.
where crustaceans live and on the season.
Chironomids – red mosquito larvae – con-
The composition of Daphnia resembles
stitute a high-protein food, which contains
freshwater shrimp: Gammarus pulex,
around 60% crude protein and 10% fat in
which contains similar amount of valu-
the dry matter. Due to the low content of
able protein. It is a good source of unsatu-
unsaturated fatty acids (approx. 14%) and
rated fatty acids, including n-3 acids, and
high content of saturated fatty acids (ap-
carotenoids. One kilogram of dry matter
proximately 28% of palmitic acid) the food
of Gammarus pulex contains about 700-
cannot be used too often, because it can
-800 mg of carotenoids (with astaxanthin
cause fatty degenerations and deficiency
share of 40%).
of PUFAs. Due to its high protein content
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FLAKES
Most universal form of food. Suitable for fish living in all parts of the reservoir. Thanks to their delicate structure they float when coming into contact with water and then slowly sink. Floating all over the tank, they allow all species, even less energetic and the ones lower in the hierarchy, to feed. You can crumble them in case you need smaller bites.
GRANULES
Concentrated dose of food in the form of granules of various sizes: granules (1.4-6.0 mm), mini granules (0.8-1.2 mm) and micro granules (0.5-0.7 mm). They are sinking and slowly sinking foods. Suitable for fish eating in the middle layers of water and at the bottom. Most granules have even surface. Thanks to their closed pores they slowly absorb water, hence do not disintegrate in water, which limits the release of valuable ingredients. Tropical offers also includes the so called “bites� granules, which have uneven surface and soften quicker, hence provide perfect feeding solution for sensitive fish and the ones which are not particularly keen to eat granules.
CHIPS
Type of granules which resemble flat disk. They sink quickly but do not disintegrate in water. Intended mostly for large species of fish. Served to smaller fish, it is nibbled and bitten piece by piece, which limits the phenomenon of fast swallowing of small granules by particularly voracious fish.
PELLETS AND STICKS
Floating foods for medium and large fish which feed at the surface of water. Pellets in the shape of balls are available in size S (3.5 mm) and M (5-6 mm). Sticks are available in size M (4 mm) and L (6 mm).
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Tropical EDU Magazine
WAFERS (DISCS)
This food is dedicated to feeding fish that live near the bottom and crustaceans. Wafers rapidly fall onto the bottom, which helps to place them exactly in bottom feeders’ favourite spots or directly into the hiding place of timid species. Wafers absorb the water slowly, hence maintain their shape in the tank. Their shape and structure allow Loricariidae fish to use their suckermouths and teeth the way they do in the wild and feed by scraping food from various surfaces.
TABLETS
Foods in the form of tablets are recommended for feeding bottom feeding fish, crustaceans (sinking tablets, adhesive and plano-convex) and fish that live in the middle layers of water, including the fry (adhesive tablets and plano-convex). Adhesive and plano-convex tablets should be adhered to the glass of the tank. All tablets fall into tiny parts in the water.
MICRONISED FOODS
Foods in the form of fine powder intended for feeding the fry. In case of big fry, for instance of live-bearing fish, micronised foods may be used from the moment young fish start to feed.
NATURAL FOODS
Dried or freeze-dried invertebrates (Daphnia, Gammarus, artemia, bloodworms, Tubifex, shrimps) rich in chitin and carotenoids. Biologically safe. Perfectly supplement ornamental fish’s diet.
SOFT FOODS
Foods in the form of various soft granules obtained through advanced and innovative production technology. Thanks to their soft texture they are more readily accepted and digested by fish.
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Raw material
Crude protein
Crude fat
Ash
Artemia ‒ adult form
60
13
12
Artemia larvae ‒ nauplii
58
20
10
Krill
70
10.4
12.6
Chironomidae
60
10
11
Daphnia
50
2.4
19
47.8
20.1
4.5
Tubifex
The content of crude protein, crude fat and ash in selected aquatic invertebrates [%] of the dry matter
Artemia salina (Artemia sp.) is a popular food for ornamental fish. It is used in its larval form (also independently hatched in house conditions), frozen or freeze-dried adult forms, or as an additive to formulated foods. Newly hatched larvae of Artemia contain 89% water, 6.7% crude protein, 2.1% fat, 1.1% ash and after drying ‒ 58% protein, 20% fat and 10% ash. Adult Artemia contains 60% protein, 13% fat and 12% ash in the dry matter.
26
Literature Bernard J.B. (1997), Feeding captive insectivorous animals: nutritional aspects of insects as food, Nutrition Advisory Group Handbook, Fact Sheet 003. Ciferri O. (1983), Spirulina, the edible microorganism, Microbiological Reviews, December, s. 551–578. Clifford Chan, (2003), Exotic Discus of the World, Clean Ace Printing Press, Singapur. Floreto E.A.T., Brown P.B., Bayer R.C. (2001), The efects of krill hydrolysate-supplemented soya-bean based diets on the growth, colouration, amino and fatty acid profiles, Aquaculture Nutrition 7, s. 33–43. Gaillard M. et al. (2004), Carotenoids of two freshwater amphipod species (Gammarus pulex and G. roeseli) and their common acanthocephalan parasite Polymorphus minutus, Comparative Biochemistry and Physiology, Part B 139, s. 129–136. Ghioni C., Bell J.G., Sargent J.R. (1996), Polyunsaturated Fatty Acids in Neutral Lipids and Phospholipids of Some Freshwater Insects, Comp. Biochem. Physiol. Vol. l14B, No. 2, s. 161–170. Hasik J. (2001), Usprawnienia dietetyczne procesów metabolicznych. Co to są fitaminy?, Postępy Fitoterapii nr 6 (2–3). Kibria G. et al. (1999), Utilization of wastewater-grown zooplankton: Nutritional quality of zooplankton and performance of silver perch Bidyanus bidyanus (Mitchell 1838) (Teraponidae) fed on wastewater-grown zooplankton, Aquaculture Nutrition 5, s. 221–227. Lutomski J. (2001), Znaczenie ziół w terapii i dietetyce, Postępy Fitoterapii 6 (2–3). Nutrient requirements of fish (1993), Committee on Animal Nutrition Board on Agriculture National Research Council, National Academy Press, Washington. Opuszyński K. (1979), Podstawy biologii ryb, PWRiL, Warsaw. Sushchik N.N. et al. (2003), Comparison of fatty acid composition in major lipid classes of the dominant benthic invertebrates of the Yenisei river, Comparative Biochemistry and Physiology Part B 134, s. 111–122. Tacon A.G.J. (1987), The nutrition and feeding of farmed fish and shrimp – a training manual 2. Nutrient sources and composition, A report prepared for the FAO Trust Fund GCP/RLA/075/ITA Project Support to the Regional Aquaculture Activities for Latin America and the Caribbean, Food And Agriculture Organization Of The United Nations, Brazil.
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27
ZOANTHIDS IN THE MARINE AQUARIUM
Bartłomiej Stańczyk Marine biologist, graduate of the Department of Invertebrate Zoology and Hydrobiology at the University of Lodz. The author of Reefhub.pl, a popular blog about marine aquaristics. Since 2018 Tropical expert on products dedicated to marine tanks – Marine Power.
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29
ZOANTHUS CORALS
commonly known as Zoas, are soft corals from the subclass Hexacorallia.
Although the term “soft” is more aquarium
CHARACTERISTICS
slang than a scientific classification, it reflects
The vast majority of Zoas grow to form a col-
quite well the fact that these corals do not
ony in which each polyp is independent. In
form a stony skeleton. However, despite the
some species polyps may grow from a com-
absence of a skeleton, Zoanthus form a com-
mon tissue known as coenenchyme or, less
pact and fairly rigid tissue of polyps unlike oth-
commonly, stolons.
er popular soft corals – for example Xenia sp.
Zoanthids usually have the form of a small cylindrical polyp – on the one end fixed to the
SCIENTIFIC CLASSIFICATION
ground and on the other ending in a clear
In taxonomy Zoanthus (Zoanthids) is a name
and colourful oral disc, which is surrounded by
reserved for a particular genus of the Zoan-
a garland of arms. The appearance of a single
thidae family, but aquarists very often use it
polyp largely depends on environmental con-
to describe all similar-looking corals in the
ditions. Two separate polyps of the same spe-
Zoantharia order (including parazoanthus and
cies may differ not only in size of the oral disc
palythoa). In the following text, I will use the
and the length of the polyp, but also in the in-
same nomenclature, but please remember
tensity of coloration.
that it is a simplification.
A polyp that grows in a stronger current and
While we are at taxonomy, while preparing
is intensely lit will grow shorter and with
this material, I came across some statements
a smaller head in comparison to the same
suggesting that Zoanthids are not corals.
polyp that grows in low light and low current.
I don’t want to go too far away from the main
Since the vast majority of corals in the Zo-
topic here, because I know that the taxonomic
anthidae family contains symbiotic Zooxanthel-
classification is always disputable. For example
lae in their tissues, Zoanthids need light to sur-
some organisms, once classified as plants, to-
vive.
day are no longer plants. (I remember perfect-
30
ly well when in primary school I had to write
EASY BREEDING
a hundred times “bacteria are the simplest
In nature, these organisms have the ability to
plants”, because I wrote on a test that bacteria
reproduce sexually and asexually. There is not
are animals...).
much research on sexual reproduction in the
Many taxonomic tables classify Zoantharia or-
Zoanthidae family, but aquarists are much
der as Cnidaria and Anthozoa corals. Maybe in
more interested in asexual reproduction.
a few years it will change, but at the moment
In Zoanthids, it takes a form of budding, in
I see no problem in calling Zoanthids corals.
which a new polyp usually grows not from the
Tropical EDU Magazine
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31
tissue of another polyp, but from the tissue
happening for a few years now, because fab-
growing on the rock.
ulously colourful varieties – often fluorescent
Until a few years ago Zoanthids were consid-
ones – have begun to appear in shops. Sales-
ered to be one of the easiest corals to keep in
people quickly discovered that they could
a marine aquarium. Together with other soft
easily make a fortune on them, and the rarest
corals, they were the standard stock of tanks
colour varieties reached a price of even several
set up by the beginners in the hobby before
thousand dollars per polyp.
they learned enough about the secrets of the
That’s how Zoanthids have come back on the
marine world to face more demanding and
table and many of the tanks dominated by their
difficult to breed calcifying corals.
different colour varieties are simply breathtak-
This ease of Zoanthids breeding is due to sev-
ing. The effect is all the more amazing as these
eral factors. First of all, they are quite resistant
corals do not require large tanks or extensive fil-
to bad water parameters, so they forgive mis-
tration systems (as SPS corals do) and with just
takes made by beginner aquarists. Second-
a few different varieties focused on a small area
ly, when they have the right conditions, they
and illuminated with additional UV LEDs, you
multiply easily and quickly cover the rock on
can enjoy truly awesome view.
which they grow. Thirdly, they are very easy
Coral breeders who specialize in ”high-end”
to frag (i.e. make new cuttings for sale or ex-
Zoanthus polyps varieties keep inventing
change). Fourth, they are relatively resistant
catchy names such as Samurai Sunrise or Ice
to disease and have few natural enemies. And
and Fire. These names, however, have nothing
finally, they do not require any special care or
to do with scientific names, and it is possible
expensive equipment.
that the same coral will be called differently by
A dozen or so years ago the offer of Zoanthids
two different sellers.
in marine aquarium shops was, to say the
Unfortunately, it often turns out that rare
least, poor. Just a few simple colour variations.
things are rare not without a reason. And so
This was probably due, among other factors, to
many of these “ultra-coloured” varieties do not
the fact that the aquarists themselves shared
grow as fast as other more popular Zoanthids.
zoas with one another, and its popularity at
But although they are still relatively easy to
one point was so great that they started to be
grow and nobody is calling them weeds any-
treated like weeds. Internet forums were full of
more, obtaining vivid and durable colours re-
questions about fish species that could con-
quires more skill than in the case of ordinary
trol the growing population of Zoanthids. This
Palythoa.
was accompanied by the problem of high nu-
So, how can we enjoy the colourful coral car-
trient levels, which caused these corals to take
pets? Let’s take a look at the requirements
on brown shades and simply become unat-
of these corals from the aquarium perspective.
tractive. WATER PARAMETERS SUITABLE FOR ZOAS
32
THE RENAISSANCE OF SOFT CORALS
As I mentioned earlier, the tissue of Zoanthids
Today, Zoanthids are experiencing a real ren-
is quite thick and stiff, which protects them
aissance in marine aquaristics. This has been
to some extent from fluctuations in water
Tropical EDU Magazine
parameters and limits the effects of chemical
If intensive lighting is used in the aquarium, for
shock. However, this does not mean that these
example because SPS corals make up a large
corals do not require stable water chemical pa-
part of the stocking density, zoas should be
rameters. On the contrary, it is the stable en-
placed close to the bottom or in slightly shad-
vironment that allows them to grow and gain
ed places (but not in dark places), for example
colours, and frequent changes in salinity and
under rock overhangs. In short: we must find
water composition will stress them and pre-
an optimal location, because these corals will
vent from showing their natural beauty.
develop smaller heads in bright light and will
Their specific requirements do not differ from
lose their brightness when it’s too dark. Luckily,
standard aquarium water parameters. These
Zoanthids can be moved from one place to an-
corals will feel good in water with stable pa-
other without any problems, so it’s quite easy
rameters – temperature: 25-27OC, salinity:
to find them the right place.
33-36 ppt, pH: 8-8.3.
As for the circulation, it should be moderate,
As far as the NO3 and PO4 nutrients are concerned, it is assumed that Zoanthids are not
but not too small. Zoanthids must under no
fond of zero levels. This is due to two facts.
rent, but only steadily washed to remove any
First of all, these corals largely base their nu-
residual detritus from between the polyps.
trition on Zooxanthellae, and these, as photo-
Zoanthus corals adapt very easily to the aquar-
synthetic organisms, need nitrates and phos-
ium situation – as long as it is stable.
circumstances be jerked off by the water cur-
phates. Secondly, having a large biomass and growing relatively fast compared to SPS cor-
ARE ZOANTHIDS AGGRESSIVE / EXPANSIVE?
als, Zoanthids especially require phosphates
Most of the Zoanthids examined have cnido-
to maintain many metabolic processes in the
cytes. However, they are not very active and ef-
growing tissue.
ficient in paralyzing potential victims. Labora-
For this reason, both Zoanthids and other soft
tory tests have shown that some species hardly
corals, for example Sinularia, Sarcophyton,
ever deliver a sting, even when directly irritated
Rhodactis etc., feel good in water with detect-
by artemia larvae.
able nitrates (about 5-10 mg/l) and phosphates
If we add to this the fact that the Zoanthids’
(0.1 g/l).
arms are rather short and stiff, we come to the conclusion that the popular zoas are not very
PLACE IN THE TANK
predatory corals. However, most Zoanthids
Although Zoanthids require light to grow, they
are equipped with cnidocytes (nematocysts),
should not be placed directly under a strong
which can potentially, although very rarely, en-
light source, for example under LED panels or
danger neighboring corals, but I have never
HQI lamps. Too much light, especially when
heard that different colour varieties stinging
given suddenly, for instance when we intro-
one another.
duce new polyps into a bright aquarium with-
It would be a long time to debate which coral
out acclimatization, can cause oxidative stress
would win the battle. There is no research on
and in extreme cases even tissue regression in
this topic and practically all knowledge is based
the coral.
on different, often contradictory information
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33
coming from the aquarists themselves. How-
However, one has to be aware that zoas, like
ever, it can be assumed that even if Zoanthids
many other corals, can, in extreme situations
lose, they can threaten other corals thanks to
detach several polyps (this phenomenon is
the relatively fast growth of the colony.
known as polyp bailout) and let them sail away
Some Zoanthids varieties can be under opti-
in order to settle in a new place. This is usu-
mal conditions quite expansive, so it seems
ally a reaction to stress caused, for example,
reasonable to place them on separate rocks –
by being put in a place with too strong water
so that they will not colonize other substrates.
current. I have observed such behavior many
It is also a good idea to bring them all close to-
times, also when there was no room for new
gether, which will increase and emphasize col-
polyps on the rock.
our differences and create a spectacular view.
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Tropical EDU Magazine
FEEDING ZOANTHIDS
additional feeding, but this does not mean
Zoanthids are animals that need to get food by
that they will not take any organic matter from
themselves. Many soft corals, due to their thick
the water. If we want to get the most beauti-
tissue, have plenty of space for Zooxanthellae.
ful colours out of corals, we have to feed them
This is why these corals make excellent use
additionally, so that they won’t need an excess
of photosynthesis as a source of food, while at
of Zooxanthellae and will get rid of some.
the same time making less use of heterotro-
Zoanthids are best fed during the day because
phy. This phenomenon has become the cause
many of them close polyps at night. Tropical
of a myth among aquarists that soft corals do
Marine Power for SPS corals in powder or wet-
not need to be additionally fed. Indeed, many
ted food for LPS corals in mini granules will
of them will survive in an aquarium without
be a perfect food for them. Zoanthids don’t
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35
actively catch sinking food so it’s a good idea
to aquarists. Personally, I’ve never used it to
to turn the circulation off for a moment and
treat Zoa Pox, but on various forums you can
gently “blow” them with food using a pipette.
come across a lot of information confirming its
Watch out not to do it too intensively, because
effectiveness.
irritated polyps close immediately. It is best to spray the food over the polyp colony and allow
DO ZOANTHIDS CONTAIN PALYTOXIN?
the powder to fall freely on the corals.
Palytoxin is one of the strongest non-protein
After several minutes, the circulation will dis-
poisons. And indeed, some corals contain a lot
tribute the rest of the food, which will be eaten
of it. It certainly occurs in three coral groups:
by other aquarium inhabitants.
Palythoa, Protopalythoa and literally a few species of Zoanthus1.
TENDENCY TO DISEASES
Fortunately the vast majority of colourful zoas
Like all other organisms, Zoanthids can suffer
are Zoanthus vitenamensis varieties and they
from some health problems. Apart from the
contain no toxin. Unfortunately, there is no
stress caused by unfavorable conditions in the
cheap and easy test for its presence, so every
aquarium (e.g. bad salinity or lighting), Zoan-
time we touch Zoanthids – especially outside
thids usually have problems for two reasons.
the water – we should use safety glasses and
The first are the organisms that parasite on
gloves, and all fragging should be done in
them, such as snails or spiders. They not only
a well-ventilated room.
irritate the corals, but also bite their tissue, which ultimately leads to the slow death of the
I hope I’ve shown you how beautiful Zoanthids
colony. The best way for unwanted guests is
can be. Their coloration is often more intense
a bath in disinfectants. It is also good to check
and varied than in other corals. That’s why
the polyp “roots” as the eggs of parasites can
I encourage all marine aquarium fans to in-
be often found there.
troduce them to their tanks – especially if they
The second is a bacterial infection known as
plan mixed reefs. However, zoas-only-tanks
Zoa Pox. The symptoms of this infection are
where rocks and bottom are covered with va-
closed polyps with signs of tissue regression
riety of colourful polyps, will be definitely most
and white “pimples” and discoloration. The
impressive. I guarantee that if you devote
best cure for all bacterial infections are always
some time and heart to them, the effect will
baths of new frags in a 3% solution of hydro-
be astonishing.
gen peroxide or in an antibiotic. A very effective antibiotic is nitrofurazone (trade name Furacin). Unfortunately, in the European Union it is not available without a prescription and pet shops can’t sell it. The second effective antibiotic is chloramphenicol. It is quite easy to get it in the form of sachets in pigeon breeders’ shops. Another effective agent for diseases caused by bacteria is Chemiclean, well known
36
A 2009 Toxicon Journal scientific study (which may no longer be up to date) reports the following species of Zoantharia containing palytoxin: Palythoa caribeaorum, Palythoa mammilosa, Palythoa tuberculosa, Palythoa toxica, Palythoa vestitus, Palythoa aff. margaritae, Zoanthus soanderi and Zoanthus sociatus. 1
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Specialist product line for marine aquaristics
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37
Kamil Hazy A biotope aquarist with experience in international competitions. Advocate of systematization of environmental aquaristics. Organizer – together with ”Aquarium Magazine” – of the Polish Biotope Contest. He offers services of consulting and arrangement of biotope, habitat and environmental aquariums. He believes that aquaria are primarily intended to meet the needs of their inhabitants.
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Tropical EDU Magazine
Biotope Aquarium – shore of a tributary to Lake Inle, Burma
INTRODUCTION TO BIOTOPE AQUARIUM
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39
Biotope Aquarium – small tributary to Rio Paragua, Bolivia
“BIOTOPE AQUARISTICS”
How many of you have heard this term when considering setting up an aquarium? Probably many.
When planning to set up a new aquarium, you usually start searching for information on Facebook, but a great number and variety of aquarium groups there can really make you dizzy. Beginners in the hobby looking for inspirations, tips and advice will be often offered
one suggestion: “Why not starting a biotope?” Many will catch on and start asking further questions and looking for information online. Unfortunately, the information they will find there and the advice they will receive from most aquarium hobbyists will have nothing to
Biotope Aquarium – shallow pond in Pantanal, Brazil
40
Tropical EDU Magazine
do with the real “biotope aquaristics”. In fact the term “biotope aquarium” itself is very often abused. It is the result of imprecise terminology that has been in use for years and the same old patterns repeated all and over again. Most of us has a tendency to oversimplification when it comes to things that require more effort but image created on the basis of these simplifications will be easily assimilable but rather unrealistic. We tend to consider biotope aquaristics a hobby for the elites, but oversimplification mentioned above makes it a “product” for everyone. After all, according to Internet guidelines, it is enough to let fish from one continent into the tank... And we already have a biotope. This approach is tempting. You can belong to these “elites” not doing anything special. If you want to find out why this approach is wrong, take a minute and read this article. WHAT IS A BIOTOPE? Let’s start with the most important thing – biotope aquaristics is in no way better than other aquaristics schools or approaches. Of course, it is different from others, but as long as we, the hobbyists, have one most important goal in mind, which is the welfare of aquatic organisms, there should never be better or worse paths to follow in aquaristics. Nevertheless, the terminology needs a bit of clarification. In order to understand the idea of a biotope
aquaristics, we must explain what a biotope is. Let’s check Wikipedia then: (the below presented definitions are translations from Polish Wikipedia) Biotope – the living environment of the biocenosis, the environmental part of the ecosystem. Originally, only the abiotic elements of the habitat were defined as the biotope. Nowadays it is often understood as an inanimate habitat altered by biocenosis. The biotope together with the biocenosis forms the ecosystem. Let’s also look at the definition of biocenosis then, because it also explains a lot: Biocenosis – a group of populations of plant organisms (phytocenosis), animal organisms (zoocenosis) and microorganisms (microbiocenosis) of a given environment (biotope), belonging to different species, but linked to each other by various ecological factors and food dependencies, forming a whole that remains in nature in a state of homeostasis (i.e. dynamic balance). The biocenosis and the biotope, i.e. the physical (inanimate) environment, form an ecosystem. KEY WORD Based on these definitions, we can see that a biotope aquarium is supposed to reflect the living environment of a particular biocenosis
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Biotope Aquarium – pond in the northern ends of Pantanal, Brazil
that occurs in the same area and is linked by different factors. Therefore, there is no concept of a biotope aquarium without a biotope-specific biocenosis. However, we should remember that you can’t recreate the entire biocenosis from a given ecosystem in an aquarium, nor can you recreate the entire biotope – this is simply impossible. And that the correct naming is to define a number of factors, to systematize and create a certain canon, approach or – if you prefer – a platform for comparison and understanding in the human environment. The term “biotope aquarium” is not a new term, it has been used in the world of aquaristics for a number of years and is so well established that it seems unreasonable to reject it, even though it does not fully describe the actual state of the aquarium. Suffice it to say that every aquarium we have at home contains some kind of biocenosis and some kind of bio-
tope, which most often do not occur in nature or do not reflect the natural ecosystem, but theoretically we can also call it a biotope tank. The most important aspect, the key word in this whole puzzle, by which most of the naming problems are caused, is the expression “to reflect”. THREE SCHOOLS At this point let’s go back to the aquarium hobbyists and their perception of biotope aquaristics. Some of them believe that there is no such thing as biotope aquaristics at all, because there is no possibility to recreate the natural environment and processes in the aquarium. Others believe that we can talk about a biotope aquarium when all its elements are taken from the natural environment. All inanimate matter, all plants and animals, and even water must be derived from one specific place. There is also the third, most balanced group,
Biotope Aquarium – slow flowing mountain stream in Guang Xi province, China
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Tropical EDU Magazine
Habitat Aquarium – sunken shrub
and probably the biggest, that gives up extremes and aims to systematize this beautiful field of aquaristics. I will try to give you an idea of the approach of this third group, based on my personal opinion as well as the opinions of aquarists from all over the world. REFLECTING THE BIOTOPE IN THE AQUARIUM A biotope aquarium must contain selected elements of the biocenosis from a particular region that we want to link with one other and provide them with a biotope as close as possible to that found in nature. And so we get back to the keyword “reflect”. A biotope aquarium is to reflect, as close as possible, in an artificial, glass environment some specific underwater
ecosystem from a particular area. The selected biocenosis must be the same as the biocenosis occurring in selected nature, and the biotope must relate as closely as possible to the biotope from nature and fulfil the same role as in nature for the selected biocenosis. In simple terms: fish, crustaceans and vegetation must come from the same place in nature, and water, substrate and elements of inanimate matter (decorations) are to provide these animals and plants with living conditions as faithful as possible to nature. SIMILAR TANK TYPES If you don’t feel confident enough to create a biotope aquarium and want to have a tank more similar to the natural underwater fish
Biotope Aquarium – floodplains in the Rio Itenez basin (Guapore), Bolivia www.tropicaledu.com
43
Habitat Aquarium – pond shore
habitats, you can consider similar types of aquariums: Environmental Aquarium – aquarium reflecting a given type of aquatic environment (e.g. black waters of South America), taking into account the biocenosis that occurs in this type of environment throughout the continent. Animals and plants used in such tanks do not have to meet in nature, it is enough if they live in a similar environments. Area Aquarium – aquarium reflecting a given characteristic area with a relatively similar environment (e.g. Lake Malawi, the Amazon, etc.)
taking into account different biotopes and biocenoses from a given geographical area, consistent within the geographical framework (one river, one body of water). Habitat Aquarium – aquarium that reflects a specific habitat (e.g. streamside, sunken tree branch, etc.) taking into account the biocenoses found worldwide in such habitat types. All these types of tanks mentioned above have one thing in common, the welfare of the animals, which is a priority in case of all. Fish and plants selected for the above aquariums do not, of course, have to be derived from na-
Habitat Aquarium – pond shore
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Tropical EDU Magazine
ture, they may come from farms. However, it is important that their color varieties and body shapes are as close to natural as possible. A WORD ABOUT APPEARANCE, ARRANGEMENT AND EDUCATION The very appearance of a biotope aquarium is often eagerly discussed as well. In my opinion, nothing stands in the way of the biotope tank to play its role and be harmonious and beautiful at the same time. A pile of branches and leaves thrown into the tank chaotically can be arranged somehow and – without losing anything of its usefulness for animals and plants – enjoy the eye of the viewers. However, it must be remembered that the arrangement of the aquarium should first meet all animals’ needs, that’s the priority. This issue is so individual that it is difficult to create any frameworks here. You should just remember about the welfare of plants and animals and the fact that an aquarium is also supposed to attract people not connected with aquaristics and at the same time to serve as an educational tool to promote given aquatic ecosystem. Furthermore, in the case of all aquariums that reflect underwater nature, it is important to keep pointing out all abnormal breeding practices educate about the destruction of the environment and disappearance of natural habitats. This rule does not apply to tanks arranged in public spaces only. We can follow this mission at home as well. Guests visiting our apartments will surely appreciate a well arranged tank with an interesting “story” behind it.
Photos by Kamil Hazy
The best natural products for black water biotopes
Quickly and conveniently enrich water with tannins and humic acids. www.tropicaledu.com
45
SNAKES SACRED AND CURSED CREATURES Dawid Krรณtki A graduate of the Faculty of Animal Breeding and Biology at the University of Agriculture in Krakow. Breeder of African and South American cichlids. An expert in the feeding and breeding of reptiles, amphibians and all kinds of invertebrates. Author of many aquarium and terrarium articles.
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Tropical EDU Magazine
Crotalus viridis capturing odour particles with a forked tongue
Since the dawn of history, snakes have
associated with the creation of life, it can
been perceived as creeping, sneaky and
be found in traditional Aboriginal art.
aggressive creatures, the embodiment of misery and death. They were perse-
All these strong emotions were probably
cuted, killed, but also worshipped and
provoked by their strange, yet function-
admired. In ancient Greece, it was be-
al anatomy, structure and a number of
lieved that appearance of snakes in the
adaptations to a hidden lifestyle. Snakes,
area around the house brought health
even though they have no limbs, move
and well-being. The Romans deliberate-
smoothly, agilely and silently, in a truly
ly created the conditions for Aesculapi-
”magical” way. Appearing suddenly and
an snakes to live in their households or
disappearing even faster, they seem like
immediate surroundings. In India, the
creatures wrapped in mystery. Their abil-
cobra was considered a reincarnation of
ity to regenerate the epidermis through
important personalities and was referred
periodic moulting gave rise to the belief
to as “naga” (hence the generic name:
that they are reborn in a new, colour-
Naja). In some African cultures, the rock
ful robe. The lack of eyelids, replaced by
python was worshipped and killing it
a clear membrane called brille, makes
was considered a serious, severely pun-
their look appear dead, motionless: hence
ished crime. Native Australians also had
the misconceptions about their ability to
their own beliefs and legends about
hypnotise their victims.
these reptiles. The rainbow serpent was
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47
ORIGIN AND EVOLUTION It is clear that animals cannot plan their own evolutionary development. In accordance with the principle of natural selection, survival of a population is determined by a distinguishing trait (or a set of traits), which guarantee(s) a greater chance of surviving in particular environmental conditions. The beginnings of snakes’ development are still unknown until this day. Their fragile skeleton and skull are difficult Solenoglypha dentition – white-lipped pit viper (Cryptelytrops albolabris)
Humans are, were and will be fascinated by these animals, and even in our century a great number of false ideas and superstitions about these creatures were developed. It is still widely believed that snakes are slippery and sticky to the touch, which many people seem to find disgusting. However, nothing could be further from the truth: their skin is dry and contains no glands producing any secretions. Children under three years of age often feel no fear of snakes. Fear develops a little later, when they are warned by adults.
to preserve and, therefore, only a small number of fossils were found by the palaeontologists. The first reptiles appeared on Earth probably about 300 million years ago. The oldest remains of these animals date back to the late Palaeozoic era, and the end of the carbon age more precisely. At that time, the dominant group of vertebrates were amphibians, but they were completely different from those that we can see today. In the Carboniferous, most areas of Earth were covered by vast swamps. The air was permanently humid while mud, rotting plants and fallen trees provided amphibians with an excellent environment. Many of them spent more and more time outside the aquatic environment and enjoyed benefits of countless invertebrate species available as food; for which they did not have to compete with other animals. Most amphibian species returned to water only to fertilise and lay eggs surrounded by a soft membrane. Their gilled larvae were similar to fish in appearance and lifestyle. They reached a form capable of living on land only after an extended period of development in water. This is a feature that most modern amphibians have preserved
Python molurus bivittatus – a pair of pythons aged 2.5 years (male 3 m, female 3.8 m)
48
until today. Although adult forms could live on land for a long time, they had to stay
Tropical EDU Magazine
Scales on the boid snake’s head are tiny and those covering the body are large and smooth
close to water or at least in a humid envi-
suggesting that reptiles were formed in
ronment, as in a dry environment the loss
a diphyletic way, i.e. from two groups of
of fluids through uncovered and porous
amphibians, or in a polyphyletic way, i.e.
skin was too great and often led to death.
from several groups of amphibians. Cur-
To further explore the terrestrial environ-
rently, a significant number of authors as-
ment they needed a number of adapta-
sume that reptiles were formed from one
tions. The most important one was de-
group of amphibians, i.e. in a monophylet-
veloping a method of protection against
ic way. Their ancestors were probably ex-
water loss. In case of snakes, it was a pro-
tinct amphibians from the Anthracosau-
tective skin cover, which eventually trans-
ria group.
formed into typical reptile scales. At the
Reptile eggs had much more yolk, contain-
same time, eggs were also protected for
ing enough nutrients for embryo develop-
the first time by hard, calcium shells. This,
ment before hatching. Such an amount
in turn, meant that internal fertilization
guaranteed greater development than in
was necessary. Animals with such features
case of amphibian larvae. This gave rep-
were no longer amphibians, but became
tiles a better chance of survival. Of course,
primitive reptiles, which could live and
their embryos also had to go through the
reproduce on land. The line leading from
early stages of development, but they
amphibians to reptiles separated from the
were shielded inside the egg by a kind
primitive strain of amphibians probably
of sack, called the amnion. The embryo
during the Carboniferous period. But am-
developed in an aqueous amniotic fluid,
phibians of this period were strongly dif-
extracting oxygen from the outside and
ferentiated and opinions on which of their
excreting carbon dioxide and metabolic
groups gave rise to the original reptiles are
products through another membrane, i.e.
not always consistent. There are concepts
the allantois. It is bound to the chorion and
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49
were the dominant creatures, until they eventually became extinct due to climate cooling at the end of the Cretaceous. Although many reptiles originating from that time have died out, today we can find confusingly similar forms of this group. The ancestors of contemporary snakes and lizards also appeared in those periods, but the remains of early Squamata are scarce. Lizards (Lacertilia) probably separated in the Triassic (240-200 million years ago) from the primitive Eosuchia order, although the oldest ancestors of modern lizards in the straight line come from excavations from the Upper Jurassic (about 140 million years ago). Small lizards and snakes (especially the latter) cause great problems for palaeontologists and are known only from scattered fragments of skulls Boids are ovoviviparous, the offspring is hatched from mucous membranes just before or during birth. The photo shows the offspring of yellow anaconda (Eunectes notaeus)
is entwined in a network of blood vessels.
and vertebrae bones. Therefore, there is currently too little data on evolution of the Squamata.
The chorion adheres directly to the shell. In the second half of Carboniferous, the climate on the globe began to change dramatically. Most of the swamps typical for this period dried up, which caused extinction of many amphibians. This was a favourable period for animals that lived on land and laid their eggs in shells. In the early Permian (280-260 million years ago), herbivores had not yet developed and reptiles were forced to devour one another. Along the development of thousands of species, this era of fierce competition saw the emergence of various adaptations for catching, tearing or swallowing prey. In subsequent periods, the Triassic and Jurassic, dinosaurs developed and mammalian-like animals started dying out. Over the next 140 million years, huge reptiles
50
The colouring of the green anaconda (Eunectes murinus), the heaviest snake in the world, perfectly masks it among Amazonian rivers and wetlands
Tropical EDU Magazine
eyelids, and with a transparent, rounded scale to protect the eye. However, the loss of hearing and limbs proved to be permanent, although some of the more primitive contemporary snake families still have vestiges of pelvic girdle. Lack of limbs and hearing was replaced by other sophisticated methods of stimulus perception and communication. All these changes lasted for millions of years. Nowadays, there are still reptiles that live underground – legless Amphisbaena, having both snake and lizard characteristics – and many legless lizards. Evolution of snakes, however, remains a mystery to some extent, as we still lack a specific link between suborders.
Snakes are swallowing the prey whole
As far as snakes are concerned, it is generally assumed that they come from lizards, but there is still a link to be found that would connect these animal groups directly. “A lost link” is particularly relevant for phylogeny of snakes, since only a few remains of old snakes were found and no animal was found between snakes (Serpentes) and lizards. One quite probable theory is that snakes evolved from lizards
CONTEMPORARY TAXONOMY It was only in the middle of the 18th century that the logical classification system of plant and animal began to develop. When Europeans started to explore continents and seas, it became clear that the number of discovered species was immense. Nowadays, there are almost 2700-3000 snake species living on Earth. They can be found in almost all environments, both in
that were the first to lose their limbs, outer ear and, almost completely, sight. When these creatures stayed underground, they started developing their unique sense of prey searching, namely using a forked tongue together with the Jacobson’s organ placed in the palate diverticulum. Perhaps in the initial phase, some species developed thermosensitive cavities on the body, the so-called thermoreceptors. As time went by, as a result of various environmental factors, some snakes, again, began to get used to living on the surface, their eyes began to develop again, but without
Thermosensitive cavities of pythons are usually located between scales in the upper lip – Python molurus pimbura
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51
Boiga nigriceps – conditionally venomous representative of Colubridae. It produces a highly toxic venom, but the way it is applied results in a small number of bites ending with introduction of venom into the wound
Class: Reptilia Laurenti, 1768 – Reptiles Subclass: Lepidosauria Haeckel, 1866 – Lepidosauria Order: Squamata Oppel, 1811 – Squamata Suborder: Serpentes Linnaeus, 1758 – Snakes Infraorder: Scolecophidia Cope, 1864 Family: Anomalepididae Taylor, 1939 Family: Leptotyphlopidae Stejneger, 1892 – Thread Snakes Family: Typhlopidae Merrem, 1820 – Blind Snakes Infraorder: Alethinophidia Nopsca, 1923 Superfamily: Anilioidea Stejneger, 1891 Family: Aniliidae Stejneger, 1907 Family: Anomochilidae Cundall, Wallach, Rossman, 1993 Family: Cylindrophiidae Fitzinger, 1843 – Pipe Snakes Family: Uropeltidae Müller, 1832 – Shield-Tailed Snakes Superfamily: Booidea Hoffsteter, 1955 Family: Tropidophidae Brongersma, 1951 Family: Boidae Gray, 1825 – Boid Snakes Family: Bolyeriidae Hoffsteter, 1946 – Mauritius Snakes Family: Pythonidae Fitzinger, 1826 – Pythons Family: Ungaliophiidae McDowell, 1987 Family: Xenopeltidae Wallach et Günther, 1998 Superfamily: Caenophidia Hoffsteter, 1939 Family: Acrochordidae Bonaparte, 1831 – Acrochordidae Family: Atractaspididae Bourgeois, 1968 Family: Colubridae Oppel, 1811 – Colubridae Family: Elapidae Boie, 1827 – Elapid Snakes Family: Viperidae Oppel, 1811 – Vipers
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Tropical EDU Magazine
the deserts and in the humid equatorial
produce different noises, such as hisses,
forests, they live in or on the soil, as well
they do not seem to be used for intra-spe-
as high in tree crowns and in the seas.
cies communication.
Modern taxonomy is based on phyloge-
Snakes have no eyelids, their eyes are cov-
ny (if known), and in those groups where
ered with a transformed, clear membrane
knowledge of evolution is insufficient,
– a callused epidermal structure that is
it is supplemented by a certain amount
removed with the moult. The tongue is
of theoretical speculation or groups are
strongly callused, clearly forked at the
made artificially.
front. It catches the odour molecules and transmits them to the palate diverticu-
ANATOMICAL FEATURES OF SNAKES
lum of Jacobson’s organ.
WITH EXPLANATION ON THE EXAMPLE
Snake saliva is usually more or less toxic,
OF SELECTED FAMILIES FROM
and the venom of some species can be
THE SERPENTES SUBORDER
dangerous even to humans. The venom is
Snakes are characterized by significant
used by scientists to produce analgesics
elongation of the trunk and lack of func-
for cancer suffering patients, neurotoxins
tional limbs. Only representatives of prim-
for neuropharmacological studies, antico-
itive families have the remains of pelvic
agulants and highly purified RNase and
girdle and, in some cases, pelvic spur on
DNase.
the sides of the cloaca. The left lung is re-
Internal organs are located in various po-
duced or absent. The rear part of the right
sitions, depending on the family and even
lung is sometimes an air reservoir, and
type. Snakes have a pineal gland, but they
snakes from about half of modern fami-
lack a parietal eye. Ovaries and testicles
lies also have the tracheal lung, which is
are elongated, there is no bladder. One
sometimes the main respiratory organ.
species is parthenogenetic.
The lack of tympanum, the middle ear is
Total length of snakes ranges from a doz-
significantly modified – the lack of Eus-
en or so centimetres to almost 9 meters.
tachian tube, the column (columella au-
All species are predators and swallow the
ris) is located in the direct vicinity of the
prey whole. Due to the fact that the an-
skeletal muscle and vascular elements.
terior part of the trachea, forming the la-
The ear cavity is reduced.
rynx and opening a gap in the rear part of
The column ends with a cartilaginous el-
the mouth bottom, can be extended out-
ement, an extra-column (extracolumel-
wards in many snakes, these animals do
la), which connects to the middle surface
not suffocate while swallowing their prey.
of the quadrate bone. Snakes are usually
The snakes that eat prey of small size,
considered deaf, but many studies show
at short intervals, maintain their diges-
that at least some can pick up vibra-
tive tract in a continuous state of activi-
tions transmitted through the ground or
ty. Yet, in the case of snakes that only eat
air. Crotalus atrox, subjected to pulsed
large prey from time to time (e.g. Python
sounds, after eliminating ground-borne
molurus), the digestive tract is inactive
vibrations, shows defensive behaviour in
between meals, so it must be prepared
85% of the tests. Although many snakes
for digestion during swallowing. Once the
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53
food is in the stomach, a metabolism in-
it. Most often, there are no venom fangs
crease absorbs as much as 32% of the en-
on the maxillary bones (Aglypha denti-
ergy coming from that meal. Speed of di-
tion), but some snakes have enlarged rear
gestion depends on the temperature and
fangs, often together with smaller ones,
size of the prey.
separated by a diastema from those at
The teeth of these reptiles are pleurodon-
the front, and a Duvernoy’s gland (Opist-
tic, but slightly modified. Each tooth lies
hoglypha dentition).
within a shallow alveolus. In the upper
About 20% of snakes have a venom gland
jaw (maxilla), the teeth are located on the
and immobile or movable venomous fangs.
maxillary bones, palatine bones and the
Immobile venom fangs: on each, relatively
lateral pterygoid plate, sometimes also on
long maxillary bone, there is one fang with
the odd premaxilla. In the lower jaw (man-
a closed groove on almost the entire length
dible) on the alveolar bone. Their number
and several others lying behind it (Prote-
is significantly different, e.g. snakes of the
roglypha dentition). Movable venom fangs:
Dasypeltis genus, which feed on eggs,
a single fang with an internal venom canal
and Tomom, which eat slugs, have only
(Solenoglypha dentition) lies on both, sig-
2-3 teeth on the maxillary bone, while
nificantly reduced maxillary bones.
others, even very closely related, more
Although Elapidae fangs are considered
than 30. Due to their structure, the teeth
immobile, in the case of a spitting cobra
are only used to hold the prey, not to tear
and Australian Acanthopis species, max-
Proteroglypha dentition in an African spitting cobra – Naja palida
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Tropical EDU Magazine
illary bones can rotate to some extent, while relatively long mamba’s fangs can even be slightly bent. Both halves of the lower jaw are connected by a ligament, which allows them to move independently. Snakes can open their mouth wide, so they can swallow a prey larger than the width of their head. In the skull of foramen magnum snakes there is no upper occipital bone, the vertebrae in the spine have a complicated structure with five surfaces of contact with the next vertebrae (there are 2 pairs of additional surfaces – zygosphen and zygantrum), which facilitates bending. A number of vertebrae ranges from 141 to over 400. There is no tail autotomy, however some have a pseudoauto-
Literature Bruins, E., Encyklopedia terrarystyki, Wydawnictwo Galaktyka, Łódź 2003. Coborn, J., Atlas węży świata, Wydawnictwo Muza S.A., Warsaw 1993. Dobrowolska, H., Gady, wydanie II – zmienione, Państwowe Wydawnictwo Naukowe, Warsaw 1990. Jaroniewski, W., Jadowite węże świata, 5th edition. Wydawnictwa Szkolne i Pedagogiczne, Warsaw 1992. Marais, J., Wielka księga węży, Wydawnictwo Książkowe Twój Styl, Warsaw 1997. O’Shea, M., Venomous snakes of the world, New Holland, London 2005. Sura, P., Encyklopedia współczesnych płazów i gadów, Wydawnictwo Fundacja, Nowy Sącz 2005. Gumprecht, A., Toenjes, E., Die Tempelotter – Tropidolaemus wagleri, Natur-und-Tier-Verlag, Münster 2007.
tomy. Photos by Dawid Krótki
Top quality organic
coconut substrates for snakes
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55
AUTUMN IN THE POND The garden pond evolves like a garden itself. It changes as the years go by, but it is also subject to seasonal changes. These natural changes resulting from the seasonality of our climate determine the procedures that need to be carried out in the pond to ensure its proper functioning.
56
Tropical EDU Magazine
CLEANING IS ESSENTIAL
PREPARING FOR WINTER
Regardless of the season of the year, the
Preparations for winter will differ between
appearance and functioning of the pond
shallow (up to 1 m) ponds and deeper ones.
are determined by the maintenance pro-
With shallow ponds, especially when their
cedures carried out inside and around it.
bottom is made of plastic moulds, the best
Keeping the pond clean has an impact on
solution is to pump out water and hide all
the formation and maintenance of biologi-
the technical equipment. Both fish and
cal balance. The pond, as a closed (general-
plants will be then overwintered indoors.
ly) artificial ecosystem, is exposed to the ac-
In turn, owners of deep ponds (above one
cumulation of organic matter, which leads
meter) must take action to allow fish and
to deterioration of water quality and smell
plants to overwinter in the pond. The first
and reducing its transparency. The growing
works can start already in September.
conditions of plants are worsening – cloudy water is poorly permeable to sunlight, which
REMOVAL OF ORGANIC MATTER
is essential for photosynthesis. Decompos-
FROM THE POND
ing organic matter absorbs oxygen, which
If shrubs and deciduous trees grow in
in extreme cases can cause the fish to go
the vicinity of the pond, you have to be
into hypothermia due to suffocation. Any
ready to remove the leaves that fall into
negligence in pond maintenance is particu-
the water. If there is a large number of
larly dangerous during winter, so autumn is
these, it is worth considering installing
a period of intensive cleaning work just to
a fine-meshed net just above the water
be prepared.
surface. When the leaves fall, you can eas-
Net to protect the pond against leaves falling from trees and shrubs
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57
Strong, well-nourished fish will have a better chance to survive winter in the pond
ily remove the net. If this is not an option,
into water. As a result, spring can greet
you must regularly remove the leaves by
you with an unpleasant view of dead fish
hand or with a vacuum cleaner. Or use
that have suffocated during winter.
a skimmer that catches floating debris on
Of course it is not possible to remove all
the surface.
organic matter from the pond unless we
Cleaning the pond of remaining organ-
plan to start a new home. So preparing for
ic matter is particularly important when
winter is about securing the pond so that
fish are to overwinter
it will wake up to life together with a new
in it. The organic mat-
season. We will not remove all organic
ter accumulated in the
matter, but we can support the function-
pond even at low win-
ing of the pond by using selected strains
ter
will
of bacteria such as Bactinin Pond. These
be slowly decomposed
live bacteria cultures support the decom-
by bacteria and fungi.
position of organic residues, preventing
These processes absorb
them from accumulating in the pond.
oxygen. In deeper layers
Using them regularly throughout the
of sediment, anaerobic
season will significantly improve pond’s
decomposition will can
functioning.
temperatures
take place and hydrogen sulphide can be released
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Tropical EDU Magazine
If leaves enter the pond, they must be removed as soon as possible
AQUATIC PLANTS
zones – especially floating plants such
Shorter autumn days and lower tem-
as spongeplant or water hyacinth men-
peratures affect life processes of aquatic
tioned above – should be removed from
plants. Some of them will die at the first
the pond when the first signs of freezing
frost. This applies to plants from tropical
due to a decrease in temperature are no-
climates, such as water hyacinth (Eichor-
ticed. If you have the right conditions, you
nia crassipes) or spongeplant (Limno-
can try to overwinter some of the plants.
bium spongia). Indigenous species can
This can easily be done with a sponge-
overwinter in the form of rhizomes, e.g.
plant, provided you have a heated and il-
pondweed (Potamogeton spp.), typha
luminated aquarium. However, due to the
(Typha spp.), common reed (Phragmites
relatively low price and rapid growth you
communis), as seeds, e.g. pondweed
can also buy several new specimens each
(Potamogeton spp.), as winter buds, e.g.
year.
pondweed (Potamogeton spp.), hornwort (Ceratophyllum demersum), and
PREPARING FISH FOR WINTER
under favourable conditions also as green
At water temperatures below 10°C, fish
shoots.
stop feeding and gradually enter the state
Death of aquatic plants causes a large
of hibernation. But before this happens,
dose of organic matter to enter the pond.
it is good to feed them well so that they
Therefore, plants from tropical climate
can store enough supplies to survive the
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59
winter. Koi Wheat Germ & Garlic Pellet –
damaged by frost. The exception is aera-
a food with garlic and wheat germs – is
tion stone, which will provide aeration of
an excellent choice for the autumn. If pro-
water. It is worth noting that the stone
vided regularly, it improves fish’s immuni-
should be submerged to a maximum of
ty and facilitates digestion. As the water
1/4 of the depth of the pond, as a deeper
temperature drops, the feeding frequen-
submergence would cause warmer water
cy and the feed rate should be reduced.
from the bottom of the pond to mix with
The food administered should be eaten
colder water from its surface. This warmer
quickly and completely.
water layer at the bottom of the pond is very important for the survival of the fish.
WINTERING FISH IN THE POND
In order to avoid the need to chop out the
In ponds deeper than one meter you can
holes in winter and risking to wake up
overwinter your fish. After cleaning, fill
the fish from lethargy, it is recommend-
the pond with water to the maximum
ed to place a float with a heater in the
level. The aim is to ensure as deep pond
water to prevent the surface of the pond
as possible make it easier for the fish to
from complete freezing and ensure gas
overwinter. If tap water is used to replen-
exchange. If necessary, special water-oxy-
ish the pond water, it is advisable to use
genating tablets can be given through
a chlorine neutralizing agent.
the hole in winter.
Before winter, also remove any electrical
Another way to oxygenate the water in the
equipment in the water so that it is not
pond during winter is to leave the shoots
Pistia stratiotes is a floating plant from tropical climate (just like water hyacinth and spongeplant) and it should be removed from the pond before winter
60
Tropical EDU Magazine
of plants such as the typha or the reed in the shore area. If we do not have them, the solution is to place a clump of straw in the pond, which will also provide a gas exchange if the pond surface freezes.
Daily improvement of immunity and easier digestion
WINTERING THE FISH OUTSIDE THE POND In the case of small, shallow tanks, overwintering fish must be carried out in a closed room. For this purpose, a suitably large container should be prepared, equipped with a filter. You need to fill the container with water partly obtained from the pond and mixed with tap water, properly treated with agents such as Antychlor Pond, which neutralizes chlorine, and Esklarin Pond, which will make the water safe for fish. Throughout the entire winter, it is worthwhile to regularly use a product with bacteria, which will help to maintain stable water parameters. When the temperature is high in the room where the fish are overwintered, they should be fed. Due to the small volume of water, it is important that the food is of high quality and is fed in small quantities. Any excess food floating for more than 30 minutes should be removed mechanically. * Work done in autumn will be rewarded with a beautiful spring pond. It will then not require much work. Healthy fish will be happy to try to spawn, and this will bring us many interesting observations for the next months. KOI WHEAT GERM & GARLIC PELLET is a food for cyprinids with the special attention to valuable koi living in garden ponds. Thanks to its unique composition with added garlic and wheat germ, it enhances fish’s condition and improves their immunity.
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61
Innovative soft granules concept The Soft Line includes granulated foods of a unique soft texture. They ensure excellent condition, intensive growth and coloration in fish. exceptional palatability rich formulas unique ingredients improved immunity of fish
Thanks to new transparent tins it will now be easier for you to choose a proper food. HERRING • CALANUS • KRILL • INSECTS • ALGAE www.tropicaledu.com
