The catfish species listed here are some of the most popular among hobbyists. These catfish The South American can be identified by the spot at the base of the caudal fish. One of the coolest little freshwater tropical fish you can keep..Trust LiveAquaria.com for the highest quality, healthiest freshwater tropical fish species in the industry for freshwater fish tanks, aquariums and more. We 've got a great selection of angels, plecos, cichlids, livebearers, tetras, and much more! Shop LiveAquaria Freshwater Fish .Catfish Varieties, catfish species list, fish guides for all types of catfish, catfish information, They are found all over the world, though primarily in fresh water, with the each fish guide to help with identification, and to aid in choosing pet fish..