Goldfish is a common wide-temperature fish, which has a long culture history in China and is usually divided into grass species, culture species, dragon species and egg species. Among them, grass goldfish is the most widely raised variety, which is not only beautiful in shape, but also easy to raise. Egg species is a popular variety in recent years, and its appearance is round and lovely.

Arowana is a large ornamental fish, and it is also an ancient primitive fish species, which originated in Southeast Asia and is rare in the wild, but the number of artificially raised fish is relatively large. As a tropical fish, it has certain requirements for water temperature, and it is best to keep it above 24 ℃. In addition, during the breeding period, male fish will keep their eggs in their mouths for protection.

Guppy is a very common small tropical fish. It has many species and rich colors. No matter which one, it has a beautiful big tail. It is worth mentioning that guppy is a well-raised ornamental fish, which has strong adaptability to the environment and is easy to breed, especially suitable for beginners to practice their hands.

Parrot fish is an artificially cultivated ornamental fish, which is also popular at present, mainly because of its bright red color, so it is very popular in China. Due to the congenital defects of this fish, the demand for oxygen is relatively high, and it needs higher dissolved oxygen to keep alive. In addition, attention should be paid to feeding and water temperature to keep its body color bright.

Koi, like goldfish, belongs to wide-temperature fish, but it is relatively large and needs a large fish tank to keep it. However, it does not require high water quality, and its feeding habits are miscellaneous, so it is easy to raise.