Ornamental fish species: red dragonet, gold dragonet, parrot fish, fortune fish, koi carp, seven-star swordfish, crocodile crocodile, fighting fish, Lanzhou goldfish, pineapple fish. Red dragonfish: subdivided into four kinds of orange, pink, crimson and blood red, of which blood red is the most beautiful and valuable, and the number is very small; gold dragonfish: also known as the beautiful hard-servant tongue fish: also known as the Asian dragonfish, gold dragonfish; Lohan fish: is a variety of American cichlid crossbreeding, improvement, curing genes, is a variety of blood of the "hybrid"; parrot fish Parrotfish: are tropical fish that live in coral reefs. Because of its bright colors, the mouth shape resembles a parrot's mouth and named; fortune fish: also known as airships, long silk perch, originating in Vietnam, Thailand, Malaysia, etc., belongs to the family of fighting fish. The fish of this family are relatively small in size, but the fortune fish is the giant of the fish in this family; Koi: biologically belongs to the carp family all over the world *** there are more than 3,700 species of 210 genera of fish in the family of carp; Seven Star Swordfish: also known as Bowback Fish, Seven Star Flying Dagger Fish, Oriental Swordfish, Flower Swordfish. The front half of the body is broad and thick, the tail is small and pointed, and the back is slightly bowed and bulging; Sharp-billed Crocodile (Sparrow Eel): is a freshwater fish with a long barrel shape. Native to the Great Lakes region of North America, belonging to the family of finch eels; fighting fish: strong, not selective, preferring carnivorous bait, they do not require high requirements for the feeding environment, there are no special requirements for water quality, feeding is very easy; Lanshou goldfish: was introduced from China, originated in our country, in the twelfth century has begun to goldfish domestication of the genetic research, after a long time to cultivate, the varieties are constantly optimized. Pineapple fish: also known as the West pay Luo fish, belongs to the Li family of fish. The body of the fish is light yellow-green, the head is darker in color, and there are small red spots on the end of the kiss. Sharks belong to the vertebrate phylum Chondrichthyes (Chondrichthyes) plate gill subclass, marine, a few species into the freshwater, for a group of fast swimming speed of medium and large marine fish. The latest research shows that the shark body contains a variety of biologically active ingredients, such as anti-cancer factor, squalene, mucopolysaccharides and so on. The body is long fusiform. Gill slits lateral, pectoral fins normal, not fused to the leading edge of the muzzle; northern fin dorsal; crooked tail type. Body fusiform, with gill slits on both sides of the head, but resembling a common fish. With few exceptions, the typical shark has hard, dull gray skin with tooth-like scales that give the skin a rough appearance. The tail is strong and powerful, asymmetrical and upturned; the fins are pointed; the muzzle is pointed and protrudes forward, with a crescent-shaped beak and triangular fangs under the muzzle. Sharks have no swim bladder and need to swim constantly to avoid sinking to the bottom