Management of Aquaculture After Floods

Summer is a season of growing aquatic animals such as fish, shrimps, crabs and clams. With the increase of rainfall, the food intake of aquatic animals increased. During this period, due to strong sunlight, high temperature and water temperature, large ingestion intensity of fish, shrimps and crabs, strong metabolism, increased organic matter in water bodies, accelerated decomposition of fermentation, and ease of use. Water quality deteriorates, so summer is also the most difficult season for aquaculture management. Recently, serious floods have occurred in many places. Floods have inundated or destroyed large areas of fish ponds, causing huge economic losses to farmers. What issues need to be paid attention to after aquaculture? The reporter visited the aquaculture expert Ye Xintai senior engineer.

Ye Xintai said that after the flood, many ponds and cages will be destroyed in varying degrees. Farmers should promptly clean up ponds and maintain cages to restore aquaculture production capacity as soon as possible. For mechanical and electrical equipment that is affected by floods, such as aerators, pumps, lighting facilities, and feed processing equipment should also be maintained and maintained as soon as possible to prevent accidents. Due to flooding and entrainment, there are often large amounts of silt in the flooded area and surrounding ponds. The farmers can use the mud pump to remove the sludge from the pond and the main inlet and outlet to restore the pond's breeding function.

Water is the source of life, especially aquaculture, but also pay attention to water quality issues. “Summer fish farming should ensure that the water quality is 'fat, live, tender, and cool'.” Ye Xintai told reporters that because of the dilution of rainwater, the water quality of the fish ponds is slim and floating. Slow breeding of organisms requires strengthening fertilization and cultivating plankton. At the same time, it starts aerators to rapidly decompose and ferment organic matter at the bottom of fish ponds and fertilize water quality. Farmers can take corresponding measures according to different aquaculture species: fish ponds mainly for cultured alfalfa, cockroach and eel, the water color should be kept green or brown, transparency is in the depth of 20 to 30 centimeters, and grasses and mackerel are mainly used. For fish ponds, the water color is grass green or yellow-brown, and the transparency is 30-40 cm deep; for fish ponds where shrimps and crabs are mainly cultivated, the focus is on improving the transparency of the water body. The water color is yellow-green or yellow-brown, and transparency is better. Control at 40 to 50 cm depth.

Since fish diseases are prone to occur after the flood, disinfection of ponds and nets is required. Disinfection can use bleaching powder (amount of 110-6), strong chlorine sugar or excellent chlorine net (usage of 0.110-6 to 0.210-6), Quanchiposa, and then use quicklime 2010-6 Quan Quan Spilled. For those ponds that have not been flooded, the water should be changed frequently and regularly sterilized. In general, disinfection should be performed once every 15 days. 5 to 7 days after disinfection, micro ecological preparations such as photosynthetic bacteria, Bacillus subtilis, and nitrifying bacteria can be applied to fishponds to improve pond water quality.

Ye Xintai said that after the flood, aquatic animals have poor health and must be fed with high-quality fresh feed and fed scientifically. First of all, we must choose fresh, palatable, nutritious and high-quality feeds for the food characteristics of different cultured species. The feed concentrates must be nutritionally complete. The forage must not contain mud and impurities. The animal feed must be sterilized. Feeding should be based on concentrate feed, supplemented by green feed, and refined and crudely matched. Feeding amount should be controlled to be enough for aquatic animals to eat 80%, and should not be fed too much, so that the residual bait will not spoil the water quality. Specifically according to the weather, water color, water temperature, aquatic animal activities and feeding conditions as appropriate, increase or decrease, flexible grasp, so that timing, quality, positioning, quantitative feeding. There are conditions to feed more artificial feed with full-priced feeds, so that it can ensure its nutritional needs, timely recovery of constitution, but also reduce water pollution, improve food utilization, and promote its healthy growth. Before bleaching, the green feed must be disinfected with bleaching powder. Vitamin C can be added to the compound feed to increase the resistance of aquatic animals to pathogenic factors.

Ye Xintai also reminded the farmers: “Because of the continuous rainfall, poor lighting conditions, poor photosynthesis capacity, low dissolved oxygen in water, and hot weather after the flood, a large amount of organic matter and other impurities on the surface are brought into ponds by the rain, and the oxygen consumption The increase in water quality causes deterioration of the water quality, which can easily lead to the lack of oxygen in the ponds. Therefore, it is necessary to strengthen the inspection of the ponds and adhere to the early, middle, and evening surveys of the ponds once to observe changes in water color, water quality, fish activity, feeding conditions, and presence or absence of floating heads and morbidity. And so on, the residual bait was found and removed in time to prevent deterioration of the water quality. In the event of an oxygen-deficiency hurricane, aerators should be immediately opened or new water should be added to avoid flooding.