A breeder feeds fish at an aquatic farm in Changxing, East China's Zhejiang Province, on July 7, 2026. The farm adopts in-pond recirculating aquaculture systems, achieving doubled yields through concentrated high-density farming in just 2-5 percent of pond water surface area. It realizes zero-discharge effluent and ecological sustainability, and meanwhile enhances fish meat quality by water current stimulation effectively. Photo: VCG