Grass carp is one of the four major edible fishes in my country and has the most outstanding returns. 1. Grass carp as a captive species can be cultured in any pond, but the proportion must be strictly controlled according to the specific conditions of the pond. Generally, for old ponds with thick silt, unguaranteed water sources, or close to the village, the amount of stocking should be controlled at no more than 120 ponds per acre, and the feed should be mainly fed with various green feeds. In order to solve the conflict between grass carp and other species competing for food, grass carp should be fed as much as possible before feeding other fish every day.

2. Main cultivation of grass carp

2.1 Pond. The silt of ponds that mainly raise grass carp should not exceed 20 centimeters. The water source is sufficient and the water quality is good. The water depth of the pond should be maintained at more than 2 meters. A pond of about 10 acres should be equipped with a 2.20-kilowatt aerator.

2.2 Fish species. Grass carp species must be neatly sized and physically strong, with a size of 100g/tail. The sizes of other matching species, especially carp species, must not be larger than grass carp.

2.3 Variety combination and stocking density. For ponds that mainly raise grass carp, the amount of grass carp put in should be controlled at about 60% of the total amount. For ponds with better conditions, 500-550 grass carp can be put per mu, along with 300 silver carp, 70 bighead carp, and 80 carp ( Or 150-200 crucian carp), and can also be paired with bream.

2.4 Feed. Mainly feed green grass or various aquatic grasses. In addition to regular feeding of barnyard grass, reedgrass, Vallisneria, and waterweed, artificially grown alfalfa, Sudan grass, ryegrass and other high-quality and high-yielding green feeds can also be fed. In addition, various weeds and vegetables, beans, melons, corn stems and leaves, etc. are all good feed for grass carp. The amount of feed should be flexibly controlled according to the weather, fish eating conditions, and water quality. It is best to eat it before evening every day. During the high temperature season in summer, grass carp should be strictly prevented from eating night grass. In addition, at around 4 pm every day, 1.50 of the weight of the pond fish should be fed with granular bait to supplement nutrition and acclimate to concentrated feeding. Grass carp puffed granule bait works well when used in conjunction with green feed. This bait can not only meet the growth needs of grass carp, but also save a lot of labor. It is also very beneficial to purifying water quality and preventing fish diseases.

2.5 Water quality regulation. The water quality for raising grass carp is very important, and the water quality should always be kept fresh and hygienic. It is required to add 5-10 cm of new water every 3-5 days to increase the vitality of the water body, increase dissolved oxygen, increase the proliferation rate of plankton, meet the feed needs of silver carp and bighead carp, and also stimulate the rapid growth of grass carp. Equipped with an aerator to increase oxygen to keep the water quality fresh and the dissolved oxygen normal. At the same time, 10-20 kilograms of quicklime is poured every half month to clarify the water quality. Transparency is best kept at 25-30 cm.

2.6 Prevent fish diseases. Bacterial enteritis, gill rot, and red skin disease are the three major diseases of grass carp. In recent years, viral hemorrhagic diseases have also appeared in some areas. In actual production, these diseases are all concurrent diseases. Therefore, comprehensive prevention and treatment methods must be adopted accordingly.

2.6.1 Completely clear the pond. Ponds that mainly raise grass carp must be thoroughly cleaned before stocking to eliminate pathogens and harmful organisms. It is best to use quicklime dry method to clear the pond, with a dosage of 75 kilograms per mu.

2.6.2 Disinfection of fish species. Fish fingerlings must be disinfected before stocking. You can soak the fish fingerlings in 3-4 saline solution for 15 minutes. You can also use 10 mg/kg bleaching powder, 8 mg/kg copper sulfate and other disinfection methods. You can also use various vaccines produced by regular manufacturers to inject immunize grass carp to enhance disease resistance.

2.6.3 Feed disinfection. All green feed is best disinfected with 5-10 mg/kg bleaching powder solution before feeding.

2.6.4 Disinfection of food venues. June-September. Disinfect the food court every half a month by dissolving 500 grams of bleaching powder in water after the fish have eaten and then splashing it around the food court. You can also use the method of hanging bags or baskets.

2.6.5 Limit appetite.

Grass carp is a glutton, and as long as the environment is suitable, its appetite is basically uncontrolled. In the high temperature season, the food intake of grass carp must be particularly limited. Generally, it is enough to feed it until it is 80% full. Grass carp should not be allowed to eat night grass, and the remaining residue must be fished out every day.

2.6.6 Disinfect the pool water and feed medicinal bait. From May to September, disinfect the pool water once every half month. Commonly used drugs and their dosages: bleaching powder 1 mg/kg, copper sulfate and ferrous sulfate mixture 0.70 mg/kg, trichlorfon 0.50 mg/kg, quicklime 20 mg/kg, The above types of drugs are used interchangeably with better results. The medicinal bait can be fed once every half month for 3 days each time. 100 grams of oxytetracycline is added to every 100 kilograms of feed, or sulfonamides, furans and other drugs can be used to make medicinal bait and fed as appropriate.