Three defenses to do well in winter fish farming management

In winter, the water temperature is low and there is little light. @#@233@#@ There is less phytoplankton in the pond water and the oxygen-producing capacity is poor. Because fish feed and move less, their constitution is relatively weak, which has a great impact on safe overwintering and growth. To ensure the safety and growth of fish in winter, the water quality regulation and management of fish ponds in winter should focus on three defenses.

Guard against shallow water. Some fish farmers believe that shallow pond water in winter is good for fish, but in fact this is a misunderstanding. In winter, when the pond water level is shallow, the water temperature changes quickly and the temperature difference is large, which will cause freeze damage to fish and is extremely unfavorable to their overwintering and growth. In winter, the water level of fish ponds must not be lower than 1.5 m, and in severe winter the water level should be deepened to more than 2 m.

Guard against oxygen deficiency. Several types of ponds can also experience pond-wide fish kills in winter: first, fish in fertilized ponds; second, fish in deep-water ponds; third, fish in cage culture. In these situations, fish often suffer from winter oxygen deficiency and floating at the surface, or even serious death, because management is neglected, causing relatively large economic losses to farmers.

Measures to prevent oxygen deficiency in fish in winter: first, control the stocking density of fish, especially in waters used for cage culture, where the cage area should be controlled within 3% of the total water surface; second, harvest in a timely manner in winter to reduce stocking density and lighten the water body load.

For pond culture waters where oxygen deficiency occurs, relevant methods can be used for emergency rescue: first, use a water pump to pump water to increase oxygen; second, splash long-acting oxygen-increasing agent; third, use oxygen from an oxygen cylinder to supply oxygen through a plastic tube to fish in cages and high-density fish ponds.

Guard against freeze damage. Cold winters often cause freeze damage to overwintering fish species. The following 4 measures for freeze prevention and temperature increase can be taken: first, set up barriers to increase temperature. On the north side of the fish pond, drive wooden or bamboo poles into the ground and surround them with woven bags or rice straw to set up artificial barriers to resist the north wind. Second, increase temperature by smoking. Whenever the north wind howls during the day, it is a sign that there will be frost at night. Wet rice straw and firewood can be piled on the bank of the fish pond and burned to produce smoke to create a warm atmosphere and reduce the degree of frost. Third, increase temperature by putting in grass. In winter, put a certain amount of aquatic grass into the fish pond so that fish can warm themselves and drive away cold in the grass. Fourth, increase temperature by adding water. In the afternoon of a sunny day with relatively high temperature, add shallow water from the shallow surface that has been warmed by the sun into the fish pond.