1, water quality requirements
The natural habitat of Penaeus vannamei is muddy seabed, with water depth of 0-72m, water temperature of 22-32℃, salinity10-25 ‰, pH value of 8.0 0.3, dissolved oxygen greater than 4mg/L, transparency of 0.3-0.5m, and the water color is green or reddish brown.
2, the preparation work before seedling.
First, the shrimp pond is cleaned up until there is no rust water in the shrimp pond. Next, clean the pond. The newly-built shrimp pond should be soaked in water for 2-3 times and then disinfected. For the shrimp pond transformed from the old pond or fish pond, it is necessary to dry the pond in the sun, clean up the silt and weeds, and then disinfect it.
Then, water is fed, and the floodgate can be opened 2-3 days after the drug is cleared, and finally, the bait organisms are cultured. When the water body is yellow-green or yellow-brown, 250g/ mu of compound Bacillus is used to inhibit the growth of miscellaneous algae, and then seedling cultivation can be carried out.
3. Selection of fry
When selecting shrimp seedlings, the quality should be strictly controlled, and high-quality shrimp seedlings should be selected for stocking. That is, when the body length is more than 0.8cm, it has the behavior of attaching to the wall, fat and complete body shape, no damage and deformity, neat group development specifications, full and transparent muscles, normal pigment in appendages, full stomach and intestines, flexible jumping, straight body when swimming, sensitive to current stimulation, strong anti-water ability and no dirt on the body surface. The survival rate is high when the total length of shrimp seedlings is more than 1.2cm.
4. Management of formative period
Water change: generally, water is not changed in the early and middle stages of aquaculture. In the early stage of aquaculture, a small amount of water is added 3-5 cm every day until the water level reaches 1.6m, and the water level is maintained. In the middle and late stage of culture, the water should be changed as appropriate according to the transparency and the change of algae phase, and the water should be changed slowly to the previous water level, and the daily water exchange rate should be controlled at 5-10 cm. And use 0.2ppm of dibromohydantoin every10-15 days to prevent progressive diseases.
Feeding method: Feed a small amount of bait and eat more meals, that is, adopt the principle of "small amount and multiple times, less days and more nights, even head and tail, reasonable collocation, alternate use, coarse first and fine later".
5. Harvest
Penaeus vannamei can be harvested after 75-95 days of culture with an average of 50-60 prawns /kg.