In summer, the weather is hot, the water temperature is high, the fish grows vigorously, the water concentration is high, and the fish is susceptible to diseases. In the hot season, it is particularly important to strengthen management. First, adjust the water quality 1. Add water to the highest water level. With the evaporation and leakage, it is necessary to refill the new water in a timely manner. Generally, the water injection is performed once every 7-10 days, each time being 10-15 cm. If the water supply is insufficient, the feeding amount and fertilizer amount should be reduced under the premise of ensuring the water color and transparency. 2. The pond should be fertilized in small quantities several times. The water should be kept reddish-brown, brownish green, brownish-green (dark green) and green, and the color of the water should be "living" (the color change is obvious); the transparency is controlled at 20-30 cm; When the water color is very strong, bleaching powder or formaldehyde can be regularly used in conjunction with disease prevention to reduce the biomass of phytoplankton (note the changes in dissolved oxygen during application). In the case of high-density cultivation, the nitrogen content in the water is generally high, and the main application of phosphate fertilizer can be applied without applying nitrogen fertilizer. 3. Adjust the pH of the pool water to maintain the pH between 7.5-8.5. A lime can be applied every 15-20 days. The amount of 20-25 kilograms per mu is used to turn the whole pool into lime milk. To improve water quality, precipitate organic matter in water, reduce oxygen consumption of organic matter in water, and promote phytoplankton growth. 4. Reasonably configure and use aerators, and install an impeller aerator based on the designed output of 5-8 mu. It can not only regulate water quality, but also increase oxygen to prevent fish floating head. The use of aerators should be based on the law of dissolved oxygen in water and the role of aerators to scientifically determine startup time and machine operating time. We must adhere to the principle of opening at noon on sunny days, open early in the morning on cloudy days, open early in the evening, open before floating heads, and open in the middle of a rainy night; the operating time must be determined according to the weather, water quality, the floating head of fish, and the area of ​​aeration machine load. The length of the Second, strengthen investment management Feeding management should implement the principle of "four decisions", that is, timing, positioning, qualitative and quantitative. The amount of bait should be flexibly controlled according to the weather, water quality, and fish eating conditions. Generally, the weather can feed more, and it can be less in rainy days. It should stop feeding before the weather is hot and thunderstorms. The water color is good, the water quality is cool, and normal feeding can be performed. When the water color is light, the amount of feeding can be increased. When the water color is too strong, the amount of feeding should be reduced and new water should be injected in time. When the fish fight for food, they can feed normally and the floating fish population decreases. When the competition is not intense, the amount of feeding can be reduced, and the reason should be found. The amount of feeding should be controlled during fish disease treatment. Third, drug prevention 1. Use bleach once every half month to prevent bacterial fish disease. Quanchiposa uses pool water to make 1ppm. 2. Disinfect the food field with bleach every month, once a day, and use 250 grams for each feeding point. Use it at 2:00-3:00 p.m. every day before feeding. Dissolve the bleaching powder and spill it around the food field and feed the fish. Can be used for 3-4 days. 3. Every ten days after entering July, a bag is hung in the food market and fish are used to eat food. They come and go in contact with the drugs released from the hanging bag to kill parasites on the fish. Each time you use it for 3-4 days, change your medicine once a day. Drugs available copper sulfate, ferrous sulfate, the amount of 100 grams per day and 40 grams and daily dose of trichlorfon 100 grams. Both drugs are used separately. Each food farm hangs 4-6 bags. 4. Oral medicine baits, mainly made from fish servings, fish blood and other medicines added to the feed to make baits, the amount can be routinely used for prevention, even feeding 3 days, 1-2 times per month.