1, the shape is different: the head of grouper is smaller, the body is longer, it is cylindrical, the back is slightly raised, the abdomen is flat, and the tail is forked like ordinary fish; Catfish's head is big and flat. Generally, its head is bigger than its body, its body is short and flat, its back and abdomen are curved, and its tail is round and fan-shaped.
2. The living environment is different from food: Jiangtuan lives at the bottom of the water layer and likes to cluster, which is warmer. It takes small fish and shrimp as bait and needs clear water to survive; Catfish have strong viability and can survive in turbid water.
3, the mouth and beard are different: the mouth of the grouper is located below the head, in a crescent shape, with four pairs, small without two long beards; Catfish's mouth is located at the front end of its head, and its kiss is short, wide and round. There must be three pairs, two of which have long beards.