To solve the problem of feed pollution in canvas pond, it is the key to plan the feed consumption reasonably. According to the size and culture density of the canvas pond, the feeding amount is accurately calculated to avoid feed residue and water quality deterioration caused by excessive feeding. At the same time, it is also very important to choose good quality feed, avoid using inferior feed such as expired and moldy, and reduce the pollution to water quality. It is necessary to clean the canvas pool regularly. Regular removal of residual pollutants such as bait and feces can effectively reduce the organic load in water quality and keep the water clean. Changing the pool water regularly is also an important measure to keep the water quality stable, which can effectively remove the accumulated wastes and pollutants and improve the water quality. The use of microbial agents is also an effective method. Microbial agents can regulate the water quality of canvas ponds, promote the reproduction of beneficial bacteria and reduce the number of harmful bacteria. These beneficial bacteria can degrade organic waste and reduce the accumulation of harmful substances such as ammonia nitrogen, thus reducing the risk of water pollution.