In A nutshell, aquaponics is an aquaculture & plant growing system where fish and plants do each other a favour: the fish waste is kindly provided to the plants, which get valuable nutrients; and the plants filter the water, providing a clean, healthy environment in which the fish can grow.
From Wikipedia:
Aquaponics (pronounced: /ˈækwəˈpɒnɨks/) is a system of agriculture involving the simultaneous cultivation of plants and aquatic animals such as fish in a symbiotic environment. In a traditional aquaculture, animal effluents accumulate in the water, increasing toxicity for the fish. It is a closed system in that the only water introduced into the system is done to replace the amount lost by evaporation. No chemical fertilizers or insecticides are used.In an Aquaponics system the water from the fish is pumped through a filtration system which consists of a sump to collect the solids and a bio filter which, through the use of helpful bacteria, turns the ammonia into nitrites which is then turned into nitrates, fertilizer. This water is then pumped to a hydroponic system where the nitrates are filtered out by the plants as vital nutrients. Then to complete the cycle, the clean water is then circulated back to the aquaculture system. The term aquaponics is a portmanteau of the terms aquaculture and hydroponic.Aquaponic systems vary in size from small indoor or outdoor units to large commercial operations. The systems are most always fresh water, as salt water systems are not very plausible because of the lack of edible vegetation that can be produced in saltwater.
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