Aquaponics (pronunciation: /ˈækwəˈpɒnɨks/), or pisciponics, is a sustainable food production system that combines conventional aquaculture, (raising aquatic animals such as snails, fish, crayfish or prawns in tanks), with hydroponics (cultivating plants in water) in a symbiotic environment. In aquaculture, effluents accumulate in the water, increasing toxicity for the fish. This water is led to a hydroponic system where the by-products from the aquaculture are broken down by nitrogen fixing bacteria, then filtered out by the plants as nutrients, after which the cleaned water is recirculated back to the animals. As existing hydroponic and aquaculture farming techniques form the basis for all aquaponics systems, the size, complexity, and types of foods grown in an aquaponics system can vary as much as any system found in either distinct farming discipline. (From http://en.wikipedia.org/wiki/Aquaponics)