Fish culture technology in reservoir

In general, the water level of the reservoir is low in the dry season in winter and spring, and the water level rises after storing and supplying water in the flood season, and the fluctuation of the water level directly affects the size of the water surface in the reservoir area. The water quality of the reservoir is generally very fertile, which provides excellent conditions for fish culture. Let's take a look at the related technology of fish culture in the reservoir.

1. Reservoir selection. The reservoir had better be located in the place where the leeward sunlight is sufficient, the dam and the bottom of the reservoir do not leak, fish bars or nets are set up in spillways and drains to remove sundries such as tree stumps at the bottom of the reservoir, and conflicts between farmers and fish may occur in the reservoir. The lowest water level of fish conservation should be determined, and the road is electrified.

2. Store water as soon as possible. The water source of the reservoir mainly comes from Rain Water, so it is necessary to plug the pipe and store water as soon as possible to ensure that there is enough water to release fish species no later than the end of March at the latest.

3. Apply base fertilizer well. Fertilization is based on the principle of not polluting the water quality. Before stocking fish fry, 200 kilograms of organic fertilizer for livestock and poultry should be put into each mu. The dry pool fraction pile is stacked in the shallow water of the slope at the bottom of the reservoir to ferment, allowing the fertilizer and water to spread freely; the impoundment reservoir digs several small soil ponds at the edge of the reservoir to pile organic fertilizer and apply it after fermentation; the fermented organic fertilizer can be directly thrown into the reservoir. It is best to apply enough base fertilizer before disinfection.

4. Timely and reasonable sowing. It is the best season for fish stocking in the reservoir before and after the Spring Festival, so the reservoir water level is small, the water temperature is low, the fish scale is compact, it is convenient for fishing operation and transportation, the fish species are not easy to be injured and infected, and the survival rate of culture is high. The key to high yield of fish culture in reservoir is to put in large size, multi-variety and sufficient quantity of high-quality fish species. The specification of herring, silver carp and silver carp is more than 9 / kg, crucian carp and carp are more than 15 / kg. In order to eliminate wild fish, 80 California perch are released per mu. The stocking amount of fish species should be determined according to the conditions of the reservoir, but it should not exceed the bearing capacity of the water body. Close culture is reasonable. Fish species should be released at once, generally 500-800 fish per mu.

5. Apply topdressing skillfully. From April to October, try not to apply organic fertilizer in order to reduce the occurrence of fish disease, and apply inorganic fertilizer instead. Ammonium bicarbonate and calcium superphosphate are the best inorganic fertilizers. The amount of fertilizer should be 3 kg / mu, once every 15 days, and keep the water brown, grass green, comprehensive yellow or sauce red according to the water quality, weather and water temperature. And there are significant changes in water color in the morning, middle and evening, and the transparency is kept around 40cm. Topdressing should avoid rainstorm time, so as not to waste fertilizer and water with the loss of flood.

6. Scientific bait. The general guiding ideology of feeding is to "grasp both ends and the middle", that is, concentrate is mainly fed in early spring and late autumn, and the quantity of bait is less, while the emphasis is from June to September in the peak fish growing season, and the quantity and quality of bait is higher. Cast snails and other fresh bait at one time in spring, 3000-5000 jin per mu. In early spring and late autumn, they were mainly fed with pellet feed or cake bait once a day, twice a day from June to September, once in the morning and afternoon, first feeding forage, and then feeding mixture or cake meal. At the same time, the bait is operated according to the method of "four determinations" (quality, quantity, timing, positioning) and "three looks" (looking at the weather, water quality, and fish eating).

7. Quicklime transfers water. The muddy water of fish culture in the new reservoir affects the respiration of fish and the reproduction of plankton. Sprinkling quicklime every 20 min 30 days not only has a good effect of settling mud and clear water, but also plays a role in preventing fish disease. The dosage is every time 20-30kg water is sprinkled on the water surface per mu.

8. Improve the environment. When the water level of the reservoir decreases gradually, the fluctuating area of the reservoir can be fully utilized, and some seeds are sown every time the water level falls, and the seeds are mainly ryegrass. Ryegrass and Sudan grass can also be planted on the dam face and slope and on both sides of the hillside, which can not only feed fish as green fodder, but also prevent the soil from being washed into the reservoir by Rain Water.

9. Reduce the pulling of the net. Trawl operation is very easy to cause sediment floating to cause water turbidity, should not trawl operation as far as possible, if you really want to trawl, it is best to choose less sunken nets.

10. Do a good job in the prevention and control of fish diseases and adhere to the principle of "giving priority to prevention, and prevention is more important than cure". Fish species should be disinfected during stocking, soak them with 4% salt water for 15 minutes, regularly sprinkle and disinfect them with trichloroisocyanuric acid, dibromohydantoin and other drugs, frequently apply quicklime, improve pH value, promote water material circulation and improve water quality, which is conducive to the growth of fish and inhibit the occurrence of fish diseases. Generally, 20 kg per mu is used, and the whole reservoir is sprinkled every 20-30 days after mixing water. When finding fish disease, prescribe the right remedy to the case in time, treat it, prohibit the use of prohibited drugs, and pay attention to the instructions for the use of drugs to prevent drug damage and economic losses.