1. Both golden crucian carp and koi are available, but there are more golden crucian carps sold outside. Most koi are mainly red and white, and the red is usually deep red.

Golden crucian carp also comes in many colors, including red, orange, black, gray, gold, and other colors, and there are some with long tails and some with short tails. It is the earliest species of goldfish and can be said to be the ancestor of all goldfish.

2. The ones with beards should be koi carp, and golden crucian carp does not have beards.

3. The one with white body and red head is koi. Of course, if there are sarcomas on the head, whether they are red or not, they are goldfish.

Differences in body shape

1. Koi fish are fat and round. The body shape of Caojin is flatter in comparison.

2. The dorsal fin of the koi is slightly behind, while the dorsal fin of the golden crucian carp is slightly forward. The color of the koi is very different from that of the koi, and there is no regular pattern. Sokin is usually fiery red in color and has a flat body, not round like koi.

The mouth of the koi carp is downward, while the mouth of the koi carp is forward; viewed from the side, the koi carp appears to be long, while the koi carp is very wide from top to bottom; the koi carp can grow to more than half a meter, and the face of the koi carp is Crucian carp is thirty to forty centimeters long, which is quite large. Bearded koi are usually fiery red in color, and their bodies are flat, not round like koi. Grass goldfish mainly include single-tailed grass goldfish and swallowtail grass goldfish. They are the original type of goldfish.

The biggest difference between koi and golden crucian carp:

1. Koi has beards, while golden crucian carp does not.

2. The tail of koi is very short, with a slight arc, and the majority of koi have long tails.

1) Golden crucian carp: Commonly known as red crucian carp or golden crucian carp, the body is spindle-shaped, the tail fin is not bifurcated, and the back, abdomen, chest, and anal fins are all normal. It has a strong physique, strong adaptability, wide feeding habits and is easy to raise. In addition to red, the body color also includes red and white flowers, five-flowered flowers, etc.

2) Swallowtail: The body is short and the tail is extremely long. The tail fin is about 2/3 or 2/1 of the total length of the fish body. The back of the tail fin bifurcates like a swallow's tail shape, hence the name swallowtail. It is a fish species with a higher degree of evolution than grass goldfish. It has a lively personality and is easy to raise. In terms of flower colors, in addition to red and white and red and white flowers, there are also glass flowers and multicolored flowers.

3) Koi has beards around its mouth. The Chinese goldfish evolved from crucian carp, which is the golden crucian carp. The goldfish is the form obtained after the evolution, mutation and hybridization of the golden crucian carp (the triangular three-dimensional wedding tail is the goldfish).

Koi fish have beards, and as long as they have beards, they are koi fishes. However, there are many characteristics that are used to determine whether a koi fish is purebred and what species it belongs to.

Koi's figure and shape are relatively plump and even, with a healthy and elegant posture (known as blessing). Goldfish generally swim relatively slowly.

The body shape of koi crucian carp is relatively thin, with a round head and short head. Compared with the body, it feels not as coordinated as koi carp. The tail fins and other drawings are longer (but now some koi carps are also very long, such as The fins of dragon and phoenix koi are super long), but koi does not look as generous as koi. In addition, koi are also characterized by their long age, which can be 70 years old, and their ability to grow very large, including 1.2M. Neither crucian carp nor goldfish grow very big.

The evolution process of goldfish = crucian carp --- golden crucian carp --- golden crucian carp --- goldfish. The period from golden crucian carp to goldfish can be said to be the biggest change in form, and the biggest change in color from crucian carp to golden crucian carp.

It can be said that there is no standard definition of the process from golden crucian carp to golden crucian carp in the middle of goldfish. There is only one definition of goldfish with a triangular tail. Both golden crucian carp and golden crucian carp have flat tails. Flat-tailed golden crucian carp has many forms. , some are very close to the golden crucian carp, and the boundary is not obvious. If you really want to distinguish between grass goldfish and golden crucian carp, then the standard is as high as distinguishing purebred koi. Only experts study it.

In fact, it is very simple. In terms of classification, grass goldfish is crucian carp. Koi, to be clear, is carp. Carp has a beard, while crucian carp has no beard.