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Aquaponics is a method of combined fish and vegetable farming that requires no soil. The farmer cultivates freshwater fish (aquaculture) and plants (hydroponics) in a recirculating water system that exchanges nutrients between the two. Wastewater from the fish serves as organic fertilizer for the plants, while the plants clean the water of fish feces and urine. The net result: a 90 percent reduction in freshwater use compared with conventional fish farming, and a significant reduction in added nutrients such as fossil fertilizers. The system can be run without pesticides and, because the fish environment is spacious and clean, without antibiotics.