1, catch adult fish: into the winter, most of the fish reached the starting size. At this time, fish farmers should pay attention to the preparation of net repair, transport means maintenance, market sales investigation and other aspects, fish should be caught in a timely manner, and seize the time to go on the market.
2, dredging pond: the pond with too thick silt first drain the pond water, manual or mechanical dredging, retain about 10cm thick silt, and then freeze the pond, which can kill pathogens and wild fish in the silt, but also promote the improvement of the bottom of the pond. At the same time, weeds must be eradicated, the walls of the sturdy ponds should be pounded, all loopholes should be plugged, and the ponds should be reinforced.
3, pond disinfection: repaired, transformed ponds should be disinfected with drugs. Commonly used disinfection drugs are quicklime, disinfection should be selected on sunny days, the method is dry pond method and water method two.
Dry pond method: use 60~75kg of quicklime per mu, and retain 8~10cm of accumulated water in the pond;
With water method: about 50cm of water depth per mu, use quicklime 100 ~ 12kg, and evenly sprinkle the whole pond after the quicklime slurry. After disinfection, fish species can generally be released for 7 to 10 days.
4. Wintering in the pond: In order to facilitate the daily management of winter, the conventional fish seed should be merged into the pond. Fingerlings and ponds are generally selected at a water temperature of 8 to 10 °C. Before merging the pond, the fish fingerling should be trained 1 to 2 times, and the net pulling action should be light to avoid fish injury and prevent the fish from being infected with various surface germs after the fish seed descends the pond.
Under normal circumstances, 20,000 to 30,000 fingerlings with a size of 10 to 12 cm can be stocked per mu of water surface. Due to the high density of fish ponds in winter, special attention should be paid to avoiding the phenomenon of dead fish caused by lack of oxygen in fish ponds.
5, stocking fish fingerlings: it is often said that "the wax water is stocked, the fish species grow strongly", the winter solstice to the Spring Festival around the time, or the water temperature at about 8 ~ 10 °C is the best time to stock fish species. In winter stocking, fish with tighter scale arrangement are generally selected, and fish with loose scale arrangement (such as bream) and scaleless fish (such as yellow eel) should choose autumn release, spring release or "one-time release, original pond rearing" stocking method.
The size of the stocked fish should be neat, large and not small, the body length is about 20cm, the scales and fins are required to be complete, swimming lively, disease-free and harmless, such fish species have strong adaptability, high survival rate and fast growth.
Fish fingerlings should be reasonably matched, stocking density should be appropriate, and fingerlings should be determined according to the pond water body environment and culture mode. When fish species are in the pond, they should be soaked with 10% salt water solution for 5 to 10 minutes or 8% copper sulfate for 20 to 30 minutes to kill the pathogens on the surface of the fish.
6. Disease prevention and control: winter fish are susceptible to water mold disease, vertical scale disease, and the occurrence of diseases is mostly caused by mechanical trauma or poor water quality of fish bodies. If fish are found to be infected with these two diseases, they can be sprinkled with water mold net, chlorine dioxide and other whole tanks, used for 2 to 3 days, and filled with new water in time.
7, mechanical maintenance: in winter to maintain the breeding machinery, rust removal, paint, oil, replace the aging line.
8. Daily management: every morning, middle and evening, each pond patrol once a day, pay attention to observe the changes in pond water color and fish activity, and make a record. The focus is on the management of pond water quality, first, pay attention to maintaining the appropriate water level of the pond, timely replenishment of new water, increase the water level, so that the water level of the fish pond is maintained at about 2 meters, and the water temperature is maintained relatively stable.
The second is to regularly regulate water quality. Fill new water regularly and discharge old water appropriately. Changes in WQOs should be monitored frequently. The dissolved oxygen volume of the water body is determined every 10 days or so. When the amount of dissolved oxygen decreases, oxygenation measures should be taken in time to increase oxygenation.