Freshwater shark, a rookie of the breeding family.

Freshwater shark is a new breed of freshwater culture introduced from abroad in Chaoyang Aquatic Science and Technology Park in 1999. It originated in Malaysia, Thailand and other places. There are two kinds of black and white sharks. The black shark is commonly known as freshwater blue shark, and the white shark is commonly known as freshwater white shark.

Freshwater sharks have many excellent traits. First of all, it has a beautiful shape, the back has a clear bulge, the abdomen is round, the head is conical, and the body surface is smooth without scales. Southeast Asian countries not only use it as an important angling fish, but also export its fry as a tropical ornamental fish. Secondly, freshwater sharks live in the middle and lower layers of the water body and have strong ability to resist hypoxia. Their adaptability and disease resistance are stronger than other fish. In addition, freshwater sharks have a very mixed diet. Under natural conditions, they feed on various rotten animal carcasses and plant debris in the water; under artificial breeding conditions, they can eat artificial feed prepared from bean cake, rice bran, corn and fish meal. It grows rapidly, and fry of 2-3 cm can grow to 1-1.5 kg that year. Freshwater shark meat taste delicious, no muscle thorn, Southeast Asia and China's Hong Kong region as valuable food fish. Freshwater sharks are therefore of high economic value.

Freshwater shark belongs to tropical fish, its low temperature resistance is poor, the differential breeding temperature is 20 to 30 degrees Celsius, the lower limit of water temperature is 1 - 2 degrees Celsius, therefore, its fry can not naturally winter in the northern region, farmers can only introduce fish species for breeding, at present, the relevant scientific research personnel of the science and technology park are stepping up to solve the breeding problem of fry, in order to reduce the breeding cost, 1-2 years later is expected to be widely promoted breeding.