Double culture technique of tilapia and mandarin fish

Tilapia do not tolerate low temperature, late autumn and early winter, when the water temperature dropped to 15℃, it can not continue to grow. In fact, tilapia ponds can only be used for half a year (May-October). Mandarin fish is different, to winter and not completely stop eating, still can continue to grow, but feeding reduced, growth slowed down. In the idle period of tilapia culture pond, mandarin fish is raised, and the seedlings are cheap and the bait fish is abundant at this stage. The mandarin fish is raised to market in May of the next year, and the price is relatively high. It has been proved by many years 'production practice that the practical technology of rotating culture of mandarin fish in tilapia pond can effectively improve the yield of pond, and the benefit per mu is more than 3% higher than that of single culture of tilapia or mandarin fish. The specific technologies are as follows:

1. Breeding of mandarin fish

Tilapia are kept until August and September, most of which have reached the market specifications (about 400 grams per tail) and can be caught on the market. When the pond is dried in late October, the mandarin fish species are bred 10 days after the pond is cleaned with quicklime, the specification is 300-400 grams per tail, and the stocking amount per mu of water surface is 300. Disinfect the fish with salt mixture before they are put into the pond.

2. Feeding bait

In the first ten days of November, feed fish were put into the pond at the same time, with the scale of 25-50 grams of cheap silver carp, bighead carp and other fish per tail. At the beginning, 150 kg was put into each mu of water surface, and then the feeding amount was gradually increased.

The feeding amount is: feeding once every 7-10 days before the end of February when it is sunny; feeding twice a week from March, feeding 15-20 kg per mu of water surface each time; increasing the feeding amount according to weather conditions in April. ensuring that the mantissa ratio of mandarin fish and bait fish is 1:5-10. The density of bait fish is too thin. On the one hand, mandarin fish are not full, on the other hand, they consume too much physical strength due to predation of bait fish, thus affecting their growth. The density of bait fish is too high, which is easy to cause hypoxia floating head. In order to ensure the year-on-year growth of uneaten bait fish, appropriate amount of vegetable cake should be fed at the same time.

3. Fertilization and water quality control

Breeding commodity mandarin fish, water body requirements dissolved oxygen rich, fresh water quality. Add new water once every 15-20 days in winter, 10-15 cm deep each time, and add new water once every 7-10 days in spring, 20-30 cm deep each time, so as to ensure that dissolved oxygen in water body is maintained at more than 4 mg per liter and transparency is maintained at more than 40 cm.

4. Disease control

Mandarin fish has strong disease resistance and basically no disease occurs in the breeding process. Before mandarin fish enters the pond, it can be disinfected by medicated bath to avoid entering the pond with illness. Feeding process should also adhere to the bait fish, to ensure adequate feed.