Photo taken on Aug. 23, 2018 shows a fish tank in OKO Farm in Brooklyn, New York, the United States. As the only outdoor aquaponics farm in Brooklyn, OKO farm is open for educational tour, farm-to-table workshop, and training program. Its aquaponics technology combines conventional aquaculture with hydroponics, by using waste water from a fish tank as fertilizer to grow plants. (Xinhua/Lin Bilin)