The practice of merging aquaculture and hydroponics. Aquaponics and hydroponics are closely related but have one very big difference......Aquaponics does not use any chemicals. Aquaponics is a completely organic, closed loop, symbiotic relationship between fish and plants. Fish waste, in the water, is converted into nutrient rich plant food by micro-organisms in biological filters. The plants take up the nutrients present in the water, then the water is returned to the fish nice and clean.