How to release fish species in winter

1. "Five changes" fish pond. "Small pond" should be changed to "big pond";"dead pond" should be changed to "live pond";"shallow pond" should be changed to "deep pond";"leaky pond" should be changed to "protective pond";"emergency pond" should be changed to "flood control pond". When renovating the pond, drain the pond water first, remove the excess sludge at the bottom of the pond after exposure, and only retain 15~20cm thick. Eradicate weeds, dredge channels, raise pond ridges.

2. Clear the pond and disinfect it. The pond shall be kept at a depth of 10cm. First, 90kg of quicklime or 4 kg of bleaching powder containing 30% chlorine shall be used for every 667 square meters of water surface to make paste and evenly sprinkle the whole pond; then, the pond shall be filled with water, and 12kg of bleaching powder shall be used for every 667 square meters of water surface to evenly sprinkle. Fish can be released only after 7 days.

3. Fertile water goes down into the pond. Apply base fertilizer 5~7 days after pond clearing. Generally, 500~700kg of fermented pig manure or 200kg of human manure are applied to every 667 square meters of water surface pond (new pond or thin pond can be applied more, fertilizer pond can be applied less or not), and then water is injected to cultivate plankton and provide natural food for fish species.

4. Species specifications. Fish species require grass, silver carp, bighead carp length 15cm, carp 13cm, crucian carp and bream more than 10cm. And rules consistent, healthy, complete scales, fin intact, thick and short tail handle, back muscles thick, bright color, strong water resistance, no disease without injury, beating frequently.

5. Let's hurry and release it early. Winter solstice to Spring Festival or when the water temperature is 8~10℃ is the best time to release@#@233@#@species. At this time, the water quality is stable, the fish body is firm, the five bodies are not easy to be injured during fishing and transportation, and the mortality and morbidity are low. At the same time, the fish species are early to be thin, adapt to the environment early, and eat early to gain weight quickly. Stocking should be carried out at noon on sunny days, frost days and rainy days with too low temperature should not be stocked to prevent frostbite fish. Fish species should be disinfected before stocking, generally soaked in 3%~5% saline for 5~10 minutes to kill pathogenic bacteria on the fish surface.

6. Reasonable mixing. According to the water quality, bait, fish species size and other conditions of fish culture waters, determine the reasonable stocking density and stocking amount. The proportion of polyculture in fish ponds with rich water is: silver carp 55%~60%, bighead carp 15%, grass carp 10%, carp 10%, crucian carp, carp, bream 5%~10%, etc. The proportion of polyculture in fish ponds with lean water is: grass carp 40%~50%, silver carp 20%, bighead carp 5%~10%, carp 10%, crucian carp, carp, bream, etc. 5%~10%. Every 667 square meters of water surface stocking amount of about 1000.

7. Strengthen management. The pond should be managed by a special person. The water should be changed once every 20 days. The water should be put first and then irrigated. The depth of water added each time should be 1.5~20cm. Quenching should deepen the water level to more than 2m deep; snow freezing should be removed and ice holes should be made to increase oxygen in the water; ponds with low oxygen content and no replenishment for a long time should be mixed with ammonium nitrate 5~6kg and calcium superphosphate 3~ 4 kg per 667 square meters of water surface and put into bags to sink underwater. At noon on a sunny day, stir the pond bottom with bamboo poles once a month. The wintering pond should be appropriately thrown with pig manure, distiller's grains, bean cakes or vegetable cakes to catch high water temperature and meet the needs of wintering fish species for a small amount of food. When the water temperature reaches 7~8℃ in spring, feed and fertilize early, cultivate fertilizer water, and promote fish to grow fast.