Knowledge of freshwater fish culture

Freshwater fish culture is to put fish species into the water body and carry out certain feeding and management, or to breed and protect the fish resources in the water body, so as to obtain the production mode of high yield fish. At present, there are more than 30 species of freshwater fish culture in China. According to the characteristics of cultured fish, water conditions, and culture measures, freshwater fish culture is divided into the following ways:

Classification according to the requirements of water temperature of farmed fish

Warm water fish culture, the general water temperature is 15-30 ℃, such as carp, grass carp, silver carp, bighead carp, crucian carp and blunt snout bream and so on; cold water freshwater fish culture: generally suitable temperature is 10-20 ℃, such as rainbow trout, fine scale fish; hot water fish culture: general suitable temperature is 18-30 ℃, such as tilapia, freshwater white Pomfret, etc.

Classification according to the conditions of aquaculture water body

According to the conditions of aquaculture water body, fish culture species and specifications, water area types and culture measures, freshwater fish culture is divided into the following ways:

1. Fish farming in still water and running water.

2. Monoculture, mixed culture and captive culture.

3. Pond fish culture, rice field fish culture, river fish culture, lake fish culture, reservoir fish culture, cage fish culture, purse seine and fence fish culture and factory fish culture.

4. Intensive breeding, semi-intensive breeding, rough breeding and so on.

Fish culture techniques in ponds

Pond fish culture is a fish culture method used in most parts of China. At present, the output accounts for more than 60% of freshwater fish culture, which has the characteristics of small investment, large income, quick effect, stable production and so on.

1. Area: generally, the area of adult fish pond is 5-10 mu, which is easy to manage. 3-5 mu is suitable for parent fish ponds, fry ponds and fish fry ponds.

2. Water depth: generally, the water depth of adult fish ponds is 2-3 meters. The overwintering pool in the north should be 1.5-2 meters below the thickest ice. The water depth of fish fry pond and hatching pond should be 1.0-1.5 meters. Fish ponds generally require a depth of 1.5-2.0 meters.

3. Water quality: abundant water sources and good water quality are the basic conditions for fish culture.

4. requirements of sediment: the best sediment of the pond is loam, sandy loam, followed by clay.

Preparation before stocking

Recuperate the pond, remove weeds and impurities from the bottom, and level the pond.

1. Clear the pond and disinfect

① soil method to clean the pond: that is, to drain the water in winter and remove the enemy damage and improve the sediment by freezing, drying and exploding the bottom of the pond.

② medicine pond cleaning: quicklime or bleach can be used.

2. Water injection and cultivation of water quality

After disinfection of the pond, when the toxicity of the drug disappears, you can live in new water. 7-10 days before fish stocking, base fertilizer is used to cultivate water quality.