The breeding cycle of Penaeus vannamei is generally from April to October, and it can be marketed after three months of rapid growth. Their growth cycle is related to seedlings, planting density, weather, daily management and disease control. What are the main points of cultivating soil shrimp?
1. Adjustment of pond water color
The ideal water color for culturing white shrimp is yellow-green or similar color formed by green algae or diatoms. The conventional control method is to apply phosphate fertilizer and ammonia fertilizer according to the proportion of pool water. In the middle and late stage of aquaculture, the water color gradually becomes darker due to the increase of residual bait and shrimp excrement. At this time, it is necessary to properly change water, inject water or add certain zeolite powder or quicklime to control the water color.
Second, it is to maintain the ecological balance of shrimp ponds
Practice has proved that white shrimp will get sick very early in ponds with little plankton, and it may get sick when the body length is only 5 cm. Generally, after the pond is disinfected for three days, 1 kg/mu of active microecological preparation is mixed into the sand, sprinkled on the bottom of the pond, and then discharged, and the bottom cooling agent is sprinkled all over the pond during water supply and fertilization, which can effectively maintain the ecological balance of the shrimp pond.
Third, control the parameters of pond water
During the cultivation of Penaeus vannamei, attention should be paid to adjusting the PH value, which should not be too high, otherwise it will increase the toxicity of ammonia nitrogen and inhibit the growth of shrimp. With the continuous growth of Penaeus vannamei, the demand for dissolved oxygen in water for cultured shrimp is gradually increasing. At the beginning, the aerator should be started intermittently according to the water quality, and then the start-up time should be gradually extended. Intensive aquaculture ponds and industrial high-density aquaculture ponds must always be opened in the middle and late stages to ensure that there is enough dissolved oxygen in the water. The transparency should be kept at about 35 cm in the early stage of cultivation and 35~6 cm in the middle and late stage. If the transparency is less than 2 cm, it is necessary to change water or add quicklime. If the transparency is too high, appropriate nitrogen and phosphorus fertilizers can be applied to adjust the water quality.
Fourth, feeding
Generally, you can feed cheap shellfish or fish paste, or you can feed some compound feed. The feeding amount should be comprehensively judged according to the shrimp size, survival rate, water quality, environment, feed quality and other factors. Feed many times a day, and the feeding amount at night accounts for 6%~7%. Visit the pond three times a day, pay attention to the water color, the activity, growth and feeding of white shrimp, visit once in the morning, adjust the feeding amount and whether to turn on the aerator at night.
5. Conditions for raising shrimps
1. First of all, if you are raising green shrimps, site selection is an important prerequisite. When raising shrimps, the surrounding water source should be of high quality, and it is best not to have other cultured shrimps near the shrimp pond, so that shrimps can have a better water source to change water during the peak growth period.
2. When raising shrimp, it is necessary to keep the PH value of the pond water between 7.8 and 8.6, but be careful not to be higher than 9.1. In addition, fresh water should be injected frequently to keep the transparency of water quality around 3-4 cm. Be sure to sprinkle quicklime solution into the shrimp pond regularly, adjust the water quality and disinfect it to prevent diseases and unsuccessful shelling. When the density of shrimp culture in the pond is too high, we should pay attention to the oxygen content in the water and install an oxygen pump.