How to manage fish ponds correctly during the period of great temperature change?

? When the weather enters the temperature change period, the water temperature decreases slowly with the decrease of temperature, and the mortality rate of sick fish in freshwater fish ponds begins to decrease. However, at this time, due to the large temperature difference between morning and evening, the incidence of pond is still high, which is prone to algae shedding, returning to the bottom, poor fish eating and lack of oxygen. Therefore, pond management should not be taken lightly. We should understand the common problems at this stage and manage them correctly to reduce unnecessary losses.

First, the temperature difference is large and the water quality is unstable. Many friends in aquaculture found that the water color of the pond changed greatly after cooling, and it was not as thick green as it was in the high temperature period. Why? Most of them are caused by the change of algae, which has strong vitality at high temperature, and there are more nutrients such as nitrogen and phosphorus in the water after eating, which is suitable for algae growth and prone to water concentration. Recently, the water temperature drops, the algae activity in the pond weakens, and the temperature difference changes greatly, which is easy to lead to algae death. Therefore, the water quality changes greatly, which will affect the feeding of cultured animals, deepen the water level appropriately, and supplement algae nutrition regularly. In the later period, there is no shortage of nitrogen fertilizer in the pond, and high-carbon soluble fertilizer "Feishuipeptide III" is supplemented to cultivate beneficial algae, reduce the chance of changing water and ensure eating. ?

Second, the temperature difference between day and night of parasites is large at this stage, which leads to water stratification or pond bottoming and lack of oxygen. If the bottom of the pond is not changed frequently, the organic matter, parasite eggs and toxic and harmful substances fermented at the bottom for a long time will turn out of the water surface, causing water quality changes, algae blooms and parasites to increase, and the current water temperature is suitable for parasite reproduction. The common parasites in this area are mainly rotifers and dactylogyrus.

Third, the water quality problem is in the temperature change period, and the water temperature is generally reduced to 26-28 C. At this stage, the fish are eating intensely, which is the prime time for feeding. However, after feeding, the digestive load of fish is heavy, and the residual bait feces in the pond increase after feeding. In addition, the weather is unstable, and it is easy to return to the bottom, bloom and change water, and the self-purification ability of water body is weak, which will lead to excessive indexes such as ammonia nitrogen and nitrite in the pond, thus affecting the normal feeding and growth of fish.

Fourth, the suggestion should be to add feed slowly first. It is suggested to add food first and then feed, and at the same time take orally "Lishengsu+Ganyidankang" to reduce the burden of fish liver and promote digestion and absorption; Secondly, we often take water shops to test water quality indicators. When ammonia nitrogen exceeds the standard, we use "Bishuian" to detoxify, and when nitrite is high, we splash "quick solution". In addition, the bottom should be changed frequently to reduce the pollution caused by the bottom.