Aquaponics is a form of sustainable agriculture that combines aquaculture, the raising of fish for consumption, and hydroponics, the raising of vegetables without soil. The farm consists of a fish tank and a grow bed. The fish help the plants, and the plants help the fish. This type of system where two very different species help each other thrive is called a symbiotic ecosystem. In this ecosystem, the fish give the plants fertilizer so they can grow quickly. In return, the plants make the water clean for the fish, so they can be healthy. The earliest form of aquaponics is seen in China, 1,700 years ago. China grew rice and fish together in one field. A more recent example is the chinampas, or “Floating Gardens”, of the Aztec Empire, 500 years ago.