Dissolved oxygen (DO) is the basis for the survival of aquatic animals. In most high-yield ponds, photosynthesis and mechanical aeration of planktonic algae are the main sources of DO, and the rest mainly come from air dissolution. In the direction of dissolved oxygen (DO), water respiration and the consumption of cultured animals are the main sources of DO consumption in culture ponds, and the rest are mainly the consumption of DO by sediment respiration.
   In culture ponds, the distribution of dissolved oxygen (DO) is uneven in both horizontal and vertical directions. During the daytime, due to the algae concentration in the downwind, the DO in the downwind is higher than that in the upwind, and the surface of the pond is much higher than that in the bottom. At night, due to the respiration of algae, the DO in the downwind is dissolved. Oxygen is lower than dissolved oxygen in the upwind. Because of the density flow, the vertical difference of dissolved oxygen in aquaculture water is not significant.
   For most aquaculture species, certain dissolved oxygen is necessary to maintain life activities. For pond culture, dissolved oxygen is one of the main water quality factors limiting the density of aquaculture. The dissolved oxygen in the ponds of the main cultured fishes in China can grow normally only when the dissolved oxygen is kept at 4 mg/l-5 mg/l. Although the main cultured fishes in China have strong hypoxia tolerance, generally the dissolved oxygen is lower than 2 mg/l, the growth of fish and shrimp living in the ponds is inhibited and their physiological activities are also affected. It will eventually lead to the increase of feed coefficient, which will affect the economic benefits of farming. A certain amount of dissolved oxygen in the aquaculture water is the key factor to maintain the material flow of the pond ecosystem. The essence of pond aquaculture water quality management is carbon management and nitrogen management. Oxygen bacteria to complete, the lack of dissolved oxygen, aerobic bacteria on the decomposition of organic matter is inhibited, organic matter in the process of incomplete oxidation of intermediate products into the water, will eventually affect the growth of fish and shrimp.