During fish farming, there are often problems that need to be addressed to add water to fish ponds. This is an effective measure to regulate water quality, and strengthening water quality control is a necessary guarantee for seizing quality and high yield of pool fish. To achieve the desired effect, note the following points in the process of adding water: First, add water at a proper time. Grasp the time for adding water, add water according to the changes in the weather, the temperature level, the water quality of the situation to master: farming ordinary fish, generally every 7 days or so to the pond water. If the weather is hot, the temperature is high, the water quality is too fat, or the weather is rainy or hot, the interval between water additions should be shortened. Second, add water in the early morning. Add water to the pond, preferably in the early morning. Because the photosynthetic activity of phytoplankton in the pool water in the night stops, the oxygen in the various organisms in the water must also consume oxygen, and it will fall to the lowest value by 3-5 o'clock in the morning. Therefore, choosing fresh water into the fish pond in the early morning has a significant oxygenation effect. During the daytime, fish ponds are generally not suitable for adding water because phytoplankton in the pool water is vigorous during the day and there is sufficient dissolved oxygen in the water. At this time, adding water not only does not increase oxygen, but causes dissolved oxygen to escape from the water. Third, add water to science. To add water to a fish pond, the following requirements must be met: 1. The injected water must be fresh, non-polluting, adequate in dissolved oxygen, and the temperature difference should not be too large. Generally, the temperature difference between the fry pool should not exceed 2°C, and the temperature difference between the fingerling ponds should not exceed 5°C. 2, the pumping water should be extracted from the upper water. Generally, the suction pipe is inserted into the water surface about 30 centimeters. Such shallow water has low organic matter content, high dissolved oxygen content, and similar water temperature to the pool water temperature. After being injected into the pond, it will be beneficial to the growth and development of the fish. 3. Before the water is added, the original pool water in the bottom part of the pond should be drained, then the new water should be injected, and the water inlet should be filtered with a dense mesh to prevent the wild fish and enemy pests from entering the fish pond. 4. When the water is added, the injected fresh water should be flushed along the upper horizontal line of the pool water. This can promote the stirring of the upper water and increase the effect of oxygen increase. The most afraid to let the water fall from a high place, in order to prevent the pool bottom sediment, humus caused by pollution of water quality. Fourth, the amount of water. Grasp the amount of water, the amount of water is too small to achieve the purpose of adding water, adding too much water is easy to make the density of plankton in the water, which affects the food intake and growth of fish. Generally, the depth of water is preferably 20-30 cm. When the lack of oxygen in the pool occurs, or when the pool water is deteriorating, 1/2-1/3 of the original pool water should be released, and fresh water should be refilled. Five, make up fertilizer water. When the pond is filled with fresh water, the water quality is often weakened and the color of the water body becomes lighter. Therefore, appropriate chemical fertilizer should be added in time to cultivate plankton, so that the pool water can remain “fat, live, tender, and coolâ€, and the transparency of the pool water can reach about 30 centimeters. To ensure the healthy and rapid growth of fish in the rich bait organisms and good water quality environment, so as to obtain a wealth of breeding benefits. (Xihua, Farmer Technology School, Longxi Town, Da'an City, Jilin Province)