How can tilapia survive the winter safely

Tilapia is a tropical fish that is not tolerant to low temperatures and will gradually die when the water temperature drops below 12 ℃. Under normal circumstances, except that tilapia can survive the winter naturally in a few areas in the south of China, other areas need to take measures to help them survive the winter. According to the practical experience of production, tilapia has the following safe wintering methods:

Hot spring water overwintering

The area of the overwintering pool should be determined according to water temperature, flow rate, topography and production scale. The water depth of the overwintering pool should be 1.5-2 meters, and the inflow and effluent should be similar to each other in order to maintain a certain water temperature and depth. If the temperature of hot spring water is very high, it should be cooled to a certain temperature through the reservoir before being injected into the overwintering pool, which has a high overwintering density. At the same time, because the water temperature is high and the amount of water is sufficient, it can strengthen the breeding and breeding of parent fish, promote the precocious gonadal maturation of parent fish, and propagate and raise seedlings earlier.

Factory waste hot water overwintering

The cooling water discharged from some factories is used to overwintering directly in the cooling pool or by building an overwintering pool. The area of the overwintering pool is determined according to the water temperature and flow rate of the cooling water, and the water depth is 1.5-2 meters. The temperature-regulating pool water can also be adjusted according to the requirements by using waste steam from some factories, and it can be put into the overwintering pool to keep warm and survive the winter. This overwintering method can make use of heat source conditions according to local conditions, with low cost and good overwintering effect.

Plastic shed earth pool overwintering

The overwintering pool is selected in the place where the leeward is facing the sun, the water quality is good and the water and electricity are convenient. The overwintering pool is best chosen from east to west, rectangular, with an area of 60-120 square meters, with a water depth of 2-2.5 meters, convenient for injection and drainage. The arched or herringbone scaffolding is built on the pool surface with steel bar or bamboo wood, and the roof is 1.8-2 meters high from the ground. It is covered with two layers of plastic film, nailed bamboo on the outside, and compacted with soil around the foot of the shed. This overwintering method can use groundwater as the source of water and keep the water temperature 16-18 ℃. It has good overwintering effect, low cost and easy to popularize. If there is no groundwater, available reservoir, stream water, through electric heater heating, increase the water temperature, generally 30 cubic meters of water should be equipped with 3 kilowatt electric heaters 1-2, this method is suitable for farmers to spend the winter in a small area.

Build glass overwintering houses for overwintering

The overwintering pond is cement land, with an area of 50-80 square meters and a water depth of 1.5-2 meters. The wintering pool is surrounded by brick walls, and the top is covered with transparent glass to form an overwintering house.

Make use of wells to survive the winter

The depth of the well should be more than 5 meters, and the water temperature should be kept above 15-16 ℃ in the coldest winter. This overwintering method is both economical and simple, and is generally suitable for farmers to keep a small amount of parent fish overwintering.