Net cage culture technology of black fish

Black fish is a common edible fish in China, also known as mullet, wealth fish, snake fish, etc., with large size, fast growth, high economic value, benthic fish, usually living in still water or micro-flow water with overgrown aquatic plants and soft sediment. All over lakes, rivers, reservoirs, ponds and other waters, let's take a look at the black fish cage culture technology!

Water area condition

The black fish has strong adaptability to the changes of environmental factors in the water body, especially to hypoxia, water temperature and poor water quality, and the requirements for water quality are not very strict. generally, the outer river waters with certain water depth and width can develop black fish culture. however, according to the living habits of black fish, micro-running water and quiet water should be selected and there is no inflow of harmful pollutants.

Cage setting

1. Cage specifications: the cage body is made of polyethylene summer flower mesh, which should be small rather than large. Generally, a small cage of 15 square meters is used. The mesh specification depends on the size of the black fish and bait fish, and the non-drilling shall prevail.

2. Cage setting: the cage is fixed in the water with bamboo at the four corners of the cage, the submerged part is 1.5 meters and the exposed part is 1 meter. In order to prevent escape, a 0.5-meter wide net should be sewn around the top of the cage mouth as an anti-escape net.

3. Stocking aquatic plants: a piece of aquatic plants (such as water peanuts, etc.) should be kept in the black fish culture cage as a habitat and concealment place for black fish. The coverage area of aquatic plants accounts for 40% to 60% of the cage area, no more than 70% at most.

Fish stocking

1. Fish species source: most black fish species come from nature, so when selecting black fish species, it is required to choose fish caught with fishing gear such as net, fish, Kowloon bag, etc., and most of the injuries caught by hook fishing should not be selected.

2. Stocking time: black fish culture generally begins to purchase fish species in winter, and the stocking work should be completed before the end of April. If the provenances are not concentrated, they can also be released one after another.

3. Stocking density: 816 black fish are stocked with a specification of 5150 grams per square meter, and the specifications of black fish in the same box are required to be uniform, so as to avoid killing each other when the bait is insufficient.

Feed feeding

1. Bait selection: black fish is carnivorous fish. at present, they are fed with fresh fresh wild mixed fish as bait, or chilled sea water small mixed fish can be used, and the feed is required to be fresh and palatable.

2. Feeding quantity: black fish culture generally starts feeding at the beginning of April and feeds once or twice a day. The daily feeding amount is 21.5% of the total weight of the fish in the box, and the annual feed coefficient is about 4.

3. Timely adjustment: black fish should have sufficient food in the prosperous and growing season to ensure that they are full to promote rapid growth, and make appropriate adjustments according to the eating conditions and weather changes of the fish.

Daily management

1. Hang some white foam on the surface of the water around the cage to prevent water rats from getting close to the cage.

2. Insist on inspecting the box every morning and find that the damaged parts are repaired in time.

3. In the season of strong wind and rainstorm, the cage should be strengthened and the box should be lifted and lowered in time.

4. lift and pull the cage body regularly to remove the attachments on the box, maintain the exchange of water inside and outside the box, and increase the amount of dissolved oxygen.