Normal phenomenon. Creek grouper walleye usually eat mainly algae, is not eat earthworms. Creek grouper generally refers to the light-lipped fish, also known as grouper, freshwater grouper, Rosefish, etc., in the biological classification belongs to the animal kingdom, phylum Chordata, order Sphenodonts, order Carp, family Carp, the light-lipped fish genus of fish collectively, the meat is tender and edible, the body color is bright, and it can be used for ornamental purposes.