The Seven Fresh Water Aquarium Fish Groups

Home aquarists divide fresh water tropical fish into seven broad groups. These groups are formed based on body shape, fin arrangement, mouth style, and other features. These groups help people who enjoy keeping fresh water fish tanks discuss their aquatic pets and identify the types of fish that will do well in their aquarium. The seven groups of fresh water fish are explained in this article.

Fresh Water Fish Group - Catfish

Catfish have flat-bottomed body designed for living at the bottom of bodies of water or your fish tank. These fresh water fish also have four to eight barbels around the low-slung mouth. Catfish are mostly dull in color and some have no scales.

Fresh Water Fish Group - Loaches

These fresh water fish are also bottom dwellers. Loaches, however, have no adipose fin situated to the rear of the dorsal fin. Some have long, eel-like bodies although some are shorter and wider. Loaches, like the catfish, have mouths that are situated on the lower portion of their faces.

Fresh Water Fish Group - Characins

Most of these fresh water fish come from South America. They have oval bodies and their mouths are situated in the midline of the body. Characins are widely varied in type. This group includes such fish as tetras and hatchetfish.

Fresh Water Fish Group - Barbs and Rasboras

This group of popular aquarium fish differ from the characins in that they have no teeth. They often have very small barbels around their mouths. These fish are usually middle level swimmers and have terminal mouths like the characins.

Fresh Water Fish Group - Tooth Carps

Most live bearing fish are included in this group. However, some are egg-laying as well. In general, these fish have narrow bodies and flat topped heads. This fish group includes platies, guppies, and mollies.

Fresh Water Fish Group - Cichlids

Cichlids are some of the most colorful of the freshwater fish kept in home aquariums. Many cichlids are wide bodied such as discus and angel fish. There are both South American and African cichlids.

Fresh Water Fish Group - Labyrinth Fish

The most popular fish in this group is the betta. These fish have a labyrinth organ which allows them to breath atmospheric air.

These fresh water fish groups give a general classification to the possible species available for home aquariums. Based on body shape, mouth position, and other characteristics, classification of freshwater fish help enthusiasts group the many types of fish.