One of the biggest mistakes I see people make in keeping an aquarium is getting two or three good-sized angelfish, then putting in a bunch of teeny neon tetras or some other small fish, then wondering what happened to the small fish. Angelfish may look peaceful, but they are still members of the cichlid family, and cichlids are carnivores. Angelfish are voracious carnivores, and they are notorious for eating smaller aquarium fish. Care should be taken to not keep angelfish with fish that can fit in their mouths, for these smaller fish will soon disappear. An aquarium, where small fish have no chance of escaping from a large predator, is not the place to take “survival of the fittest” into consideration; that’s just being cruel to the smaller fish. Otherwise angels can get along quite well with other fish their own size. Research your fish before purchasing!