Matters needing attention in winter culture of tilapia

1. Keep the pond water level stable

Properly raising the water level and increasing the water capacity in the cold winter season can not only maintain a relatively stable water temperature, but also improve the water quality conditions, and the water level of the fish pond should be kept at about 2 meters. When the water level drops by 10 to 15 centimeters, fresh water must be replenished to keep the water level and water quality stable.

2. Adjust the water quality regularly.

Ponds with water sources should be injected with new water every 10 to 15 days, adding 20 to 30 centimeters of new water, and properly discharging old water; sprinkling lime slurry every 15 to 20 days to increase the calcium concentration of the water body; and applying more phosphate fertilizer in about 20 days to increase the phosphorus concentration in the water and enhance the cold resistance of fish. Ponds equipped with aerators open from 12:00 to 2 p.m. on sunny days, promoting the circulation of surface and bottom water, making dissolved oxygen uniform and reasonable, and increasing fish appetite and disease resistance. When the weather is bad (muggy, rainy, etc.), the aerator should be added at night, usually from midnight to dawn.

3. Timely repair of damaged fishery facilities such as greenhouse, strive to reduce the loss of overwintering aquaculture objects, and do a good job in anti-freezing of fishery production facilities. In continuous rainy days, thicken the film on the windward side and lengthen the pillars of the greenhouse.

4. Properly reduce the density of fish culture to prevent the phenomenon of anoxic fish death due to the high density of fish.

5. rational feeding to improve disease resistance.

In the cold winter, feed concentrate properly to supplement the energy of fish life activities and improve the survival rate. When the water temperature is above 5 ℃, it is generally fed once every 3-5 days, and the daily dosage is 0.5%-1.0% of the fish body weight. When the water temperature rises above 8 ℃ on a sunny day, the fish activity will be enhanced, and the feeding amount should be increased appropriately.

6. Minimize the operation

In addition to ensuring the special requirements of market supply, minimize production operations. In the severe cold period, suspend fishing operations, try to avoid fishing ponds, parent fish ponds and other operations, so as to avoid fish body damage.

7. Strengthen disease prevention and control.

In the cold winter, due to the low water temperature, the immunity and disease resistance of fish are decreased, and they are vulnerable to infection and invasion by fungi (water mildew) and parasites (myxosporidiosis, oblique tube disease, melon disease, third-generation insect disease, anchor flea). Strict disease prevention measures should be taken and water bodies should be disinfected regularly.