Penaeus vannamei is commonly reared for two years each year. In July and October, the price is relatively low during the peak season and the price of shed shrimp is higher. In winter, the lowest water temperature in some areas of Guangdong has dropped to 7-8°C, and the management of shrimp culture in Wenpeng is particularly important.
1, water temperature, water level issues: in principle to maintain above 22 °C, 18-20 °C time can not be maintained too long (2-3 days). In the early stages of stocking, add water (with storage or filtration) no more than 5 cm. The cold wave is coming to pay attention to water storage and sealing pond insulation.
2, salinity and algae problems: 1-1.5 salinity should be selected as the control range, are conducive to maintaining the osmotic pressure of shrimp and the growth of green algae (such as salinity above 3 is conducive to the growth of diatoms, was dark brown). Pay attention to adding salt when changing water or adding fresh water, reducing stress, and paying attention to the small amount of air exchange in greenhouses. It is unfavorable to convert diatoms and green algae, and if necessary, human control is needed.
3, water quality control issues: to pay close attention to the growth of zooplankton, the increase in the number of fibrids can be applied to net and polyculture of 30 fish / mu small size control. If there is floating, poisonous algae, such as the appearance of the copper-green microcystis, reddish-brown dinoflagellates, chromium copper can be cast, while taking into account the wind tail pool water.
Continuous oxygenation, to ensure dissolved oxygen above 5mg/L, prevent white shrimp hypoxic floating head. If necessary, install a mobile sunroof on the roof. When there is a contradiction between ventilation and insulation, the former should be prioritized. Diligently inspect other important physical and chemical factors in the water, and take corresponding measures to maintain the pH value of 7.5-8.5, the water temperature of 22-28 °C, and the total ammonia nitrogen content of 0.6mg/L or less.
4, feeding problems: should choose to feed high-quality feed. After the seedlings are fed with 0.1 kg/ten thousand pigs, the dosage should be increased every 5 days. In principle, the feeds in the middle and later stages should be “not much less†and “a small number of times†in principle. The daily amount should not exceed 3.5% of the shrimp weight. . Diligently inspect the food table, and do not feed the leftover material to make the bottom matter deteriorate from the fertilizer, exacerbating the pollution of the water body itself. In general, there are 2-3 food preserving stations in each pond. The discharge amount of each food table is 3% of the feed amount. The standard of 1.5 hours of basic food and 80% of shrimp is sufficient. Lower water temperature, water change (sputum shell), low dissolved oxygen, etc. can be considered less feeding, test feeding.