1. Eco-environmental conditions of aquaculture. The natural ecological environment of freshwater fish culture should be fresh and excellent, free from any pollution, and rich in water resources to ensure continuous water supply all the year round. After testing, the pH value of aquaculture water in these areas is about 7.2, the biochemical oxygen consumption is less than 0.2 mg/L, and the dissolved oxygen is more than 9.0 mg/L. Other sanitary indicators are better than the national standard "Water Quality Standard for Pollution-free Food Freshwater Culture".
2. Fish socks. Fish ponds should be cleaned and disinfected about 0/5 days before stocking. Mix 0.3 kg of quicklime or 20 g of bleaching powder with water per square meter of fish pond and spread it all over the pond. Drain the pond water after 2-3 days, sun for about 10 days, and then feed the water for stocking. Freshwater fish are mainly grass carp, with a small amount of bream, carp and herring. The stocking time is from beginning of winter to Spring Festival every year. The size of fingerling requires the body length to be above 15cm, and the tail weight of grass carp is about 250g g. The stocking density is generally about per square meter 10- 13 grass carp species.
3. "sanding" feeding. The feed of freshwater fish is mainly natural or artificially planted green feed, supplemented by other fish feeds such as rice seedlings and malt, and no compound feed is fed. Timing: twice a day, 8:00-9:00 am and 3:00-4:00 pm 1 time; Qualitative judgment: green feed is fresh, delicate and pollution-free, while other feeds are fresh; Quantification: the fish is eight points full, that is, the feed is eaten up by the fish in about 3 hours.
4. Tap water regulation. Regulating flow is an important measure for the management of freshwater fish culture with small area and high density. In principle, the flow can be grasped according to different seasons.
Spring: The physical strength of fish is poor after overwintering, so it takes an adaptation process for fish to change from still water to flowing water, and it needs to live in slow-flowing water for a period of time. The exchange capacity of pool water is generally controlled at 1-2 times a day.
Summer: It is a season with abundant fish and high oxygen demand, and the exchange capacity of pool water reaches 3-5 times day and night.
Autumn: It is necessary to properly control the amount of running water, and the exchange amount of pool water is about 2-3 times a day, which will not excessively consume the physical strength of fish and is conducive to wintering.
Winter: low water temperature, low fish activity and slow metabolism. If a small amount of running water is given, the exchange capacity of pool water can reach about 1 time, every day and night.