Difference between traditional aquaculture and aquaponics: Compared to aquaculture, aquaponics systems do not have a build-up of wastes in the system that causes the
water to become toxic. Aquaponic systems utilise this waste, with the bacteria converting the ammonia into nitrites and nitrates, which the plants then consume as their main nutrient source.
Aquaculture Aquaculture is the farming of aquatic organisms such as fish and shellfish for consumption and can refer to the cultivation of both marine and freshwater species in land-based or openocean production. Up to a third of the water in a closed aquaculture system needs to be replaced every week due to the build-up of ammonia and fish waste. The water temperature can be maintained for the specific species, such as warm water (28˚C) for tilapia and cold water (12 - 14˚C) for trout.
Aquaponics Definition
Aquaponics is the symbiotic cultivation of plants and aquatic animals in a recirculating environment emulating a natural bio-system.
Water use
The water should never be replaced as it is filtered and cleaned by the good bacteria and plants in the system.
Temperature
The temperature needs of the plants should also be considered and a balance should be reached to keep the fish and plants happy. Generally, plants like 23˚C, which will be fine for tilapia.
Aquaculture
Tilapia A tilapia needs 1% of its body weight in feed every day. The better the quality of the feed, the better the production and taste. About 22 grown tilapias per 1 000 litres is the norm.
Water quality should be managed intensively.
Production
Ease of maintenance
Conclusion Hydroponics and aquaponics are two types of methods used in agriculture to grow plants on water. Chemical nutrients are used in the form of fertilisers in hydroponics, while fish waste is used as the source of plant nutrients in aquaponics. The main difference between hydroponics and aquaponics is the type of nutrients used in each method. Primary benefits of aquaponics are: • Aquaponics use 90% less water to grow the same amount of vegetables as in any other growing system. • No water goes to waste. The water is continually recirculated. • Aquaponic systems can be built on non-arable land that can’t be used for conventional agriculture; therefore cheaper land. ProAgri Zambia 32
The need stays the same and ultimately the nutrients in the fish feed will also be utilised by the plants.
Fish feed
Up to 150 tilapias per 1 000 litres will be quite happy in aquaponics because clean water continuously circulates through the dam.
Fish feed pellets
Once the system is in balance, management is easy.
• Fish is part of the equation – the fish convert the fish food and provide the nutrients and ammonia. The fish is sold once they reach market weight, covering the running costs. • Vegetables in the DWC system are harvested daily with new plants also being transplanted daily, providing a steady cash flow from the start. • Systems can be erected close to cities, highways and the market, saving a lot on transport costs. • There is a growing demand for healthy food produced without chemical fertilisers, herbicides and pesticides. Aquaponics is the answer. Statistics of aquaponics compared to traditional farming are: Reduced water usage – up to 90% Increased yields – up to 30% Accelerated plant growth – up to 200%
Aquaponics fish tank
Sources: https://hydrotower.org/2018/06/24/ why-aquaponics/ http://pediaa.com/difference-between-hydroponics-and-aquaponics/ Kleinskuur Aquaponics Training Manual; Introduction to Aquaponics, 2017, Bremner, CD & Bremner, A.
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