Second, timely down the pond. The fry is hatched from the fish eggs for 4-5 days. The fins are formed and the lumbar spots are clearly visible. The fish can swim normally and can cultivate food by themselves.
Third, sunny seedlings. On sunny days, the temperature of the pond water is higher, the dissolved oxygen is more, the fry is very vigorous, and the growth and development are fast.
Fourth, fry single raising. The fish fry hatched in the same batch should be kept in a single pond, especially grass carp and catfish, and must not be raised in large or small sizes.
Fifth, fertilizer underwater pond. In the first 3-5 days before the fry of the fish, 250-350 kilograms of livestock manure per acre is applied, and there are more facilities for the new ponds and thin ponds, and less for the fertilizer ponds and old ponds.
6. Clear the enemy and pests. Before the fish fry are stocked, the ponds are pulled 1-2 times with a dense mesh to remove insects, cockroaches, wild fish, and other contaminants.
Seven, adjust the water temperature. The difference between the temperature of the water in the fish fry in Xiatang County and the temperature of the pond must not exceed 2°C. If the temperature difference is too large, the pond water temperature must be adjusted.
Eight, fish raising. If the fry of long-term closed transportation is transported to the edge of the pond, do not immediately put it under the pond. Hold it in the pond water for a period of half an hour and then open the pond.
Nine, pay attention to the wind direction. When stocking fry, you have to stand up and slowly stock up.
First, clear pond disinfection. There are two ways: (1) dry pond method. Dry or drain the pond water, apply 75 kg of lime to the bottom of the pond per acre, and apply water one day after the application. (2) With water law. Each kilogram of water depth per meter of lime used 150 kg of lime, and the lime was watered with a slurry and the whole pond was sprayed evenly. After the toxicity of lime disappears, the fish is released.