Grass carp is distinguished from wild grass carp and forage grass carp mainly from three aspects: mouth, scale color and fin, and the main difference is color.

1, judging from the mouth: for example, the edge of the lower lip in the mouth of wild grass carp is nearly white or reddish, while the feed fish is bluish gray;

2. Judging from the color of scales: the scales of wild grass carp are usually reddish, but those of feed fish are bluish gray;

3. Distinguish from the fins: the pectoral and ventral fins of wild grass carp are slightly grayish yellow, the other fins are light gray, and the fins of feed fish are slightly red. Wild grass carp is small and slender. Domestic grass carp is huge.