A, anti-shallow water

Winter rain less, easy to cause the water level of fish ponds to reduce; some fish farmers like to put the fish pond water shallow, want to make the fish can be in the shallow water in the sun and achieve the purpose of warmth. In fact, in winter, the pond water is shallow, the water temperature changes quickly, the temperature difference is large, the fish growth is unfavorable.

Second, anti-hypoxia

Normally, hypoxia flooding occurs mostly in summer and fall during the high temperature season. And winter is rare. But there are several environments in the winter are also prone to hypoxia dead fish: one is the fat water fish ponds; two is a deep pool of dead water fish ponds; three is the net box culture. And summer and fall should be strengthened to prevent and curb the phenomenon of hypoxia flood pond dead fish.

Three, anti-freezing

The cold winter often makes the overwintering of fish species by freezing, you can take the following five ways to avoid the cold to increase the temperature: 1, set up barriers to avoid damage. In the north side of the fish pond with wooden and bamboo stick stakes surrounded by woven bags or straw straw, set up an artificial barrier to resist the north wind. 2, manure warming. Each mu of water surface cast animal manure about 500 kilograms. The use of fertilizer fermentation, decomposition, the release of heat to raise the water temperature; 3, smoking warmth. Whenever the north wind howling during the day is a precursor of frost at night, can be wet straw, firewood piled up on the banks of the fish pond fire smoke to create a warm atmosphere, weaken the degree of frost; 4, put the water plants. In winter, put a certain number of water plants into the fish pond, so that the fish in the grass to warm up and drive away the cold; 5, water injection to increase the temperature. In the high temperature sunny day afternoon will be shallow surface of the sun warmed shallow water into the fish pond.

Four ways to increase oxygen in winter fish farming

Low water level in fish ponds in winter, especially when the water surface is frozen, the pond water is prone to lack of oxygen, which can lead to fish suffocation and death in severe cases. During the wintering period, we should adopt measures to increase oxygen according to local conditions to ensure that the fish can pass through the winter safely.

1. Biological Oxygen Enhancement Inject fertilized water rich in phytoplankton into the fish pond before the ice closure, and inject no more than one-fifth of the water into the fish pond, so as to reoxygenate the pond water with the oxygen released from the photosynthesis of the phytoplankton. If the water is thin, apply 0.5 to 1 kilogram each of urea and calcium perphosphate per mu, and do not apply organic fertilizers. Fertilizer should not be applied too early, preferably before freezing, to avoid premature algal bloom, lowering the oxygen content of the water later.

2. Injecting water to increase oxygen During the winter, if the fish pond lacks water or oxygen, you can directly draw water into the pond. If the oxygen content of the water source is low, the water can be injected into the pond after going through a certain flow and drop to raise the oxygen content to enhance the oxygenation effect. Water with excessive iron content should not be directly injected into fish ponds. It should be injected into fish ponds in small quantities only after it has been exposed to sunlight for a certain period of time, and has undergone oxygenation and starching. It is better to inject water to replenish oxygen early to prevent too much water or too long injection time due to lack of oxygen, which will lead to rapid changes in the temperature of the pond water.

3. Air-filling to increase oxygen Use an air pump to press air into a hose placed under the ice. Connect a sand filter at the top of the hose or directly pierce many small holes on the hose to let the air diffuse into the water in small bubbles, so as to increase the contact area between the air and the water, and to increase the oxygen content of the pond water. If necessary, use the oxygen cylinder to send pure oxygen directly through the hose to the water under the ice for oxygen supplementation.

4. Chemical Oxygen Enhancement Small bodies of water such as pools and tanks in greenhouses can be oxygenated with chemical agents during winterization. Suitable chemical oxygen enhancers include ammonium persulfate, calcium peroxide and hydrogen peroxide. Ammonium persulphate, 10g per cubic meter of water, is not harmful to fish. Calcium peroxide and hydrogen peroxide can be used at 10-20 ml per cubic meter of water, and the dosage should not be too large to avoid harming the fish.