Killifish are a large family of freshwater fish comprising over a thousand different species. Most species are no more than an inch or two in size.

There are more than 250 species of Lake Tanganyika cichlids that have been identified, in a wide variety of colors and patterns.

Tetra are a species of tropical fish extremely popular in the aquarium trade. There are over 150 different species of tetras, most have small bodies.

Koi are one of the most popular types of pond fish. Their bodies, which are long and powerful, are very similar to that of the wild carp.

The species known as surgeonfish belong to the Acanthuridae family. Surgeonfish vary greatly in size from one species to another.

There are several species of fish that carry the ""drum"" name. With more than 250 species, drum fish exhibit a wide range of colors and patterns.

Loaches are a large family of highly intelligent freshwater fish. There are over 200 different species and they are characterized by their eel-like bodies.

Pipefish are a species of saltwater fish related to seahorses. However, the pipefish''s body, unlike the seahorse''s, is long, straight and snake-like.

African Tiger Fish are a large and predatory species of fish. Their bodies are powerful and streamlined, enabling them to move with fast bursts of speed.

The name Minnow is given to freshwater fish belonging to the family Cyprinidae. These fish are fairly small and they are generally very peaceful.

The Moorish idol is closely related to surgeonfish. These fish are characterized by their vertically compressed, disk-like bodies and bold colorations.

Referred to as breams, sea bream are a group of saltwater fish belonging to the Sparidae family. Most are found in tropical to temperate marine waters.

Wrasse are large family of saltwater fish made up of over 600 different species. They are also one of the most popular species of marine aquarium fish.

Platies are fairly small fish, growing no more than 3 inches long, and they are very peaceful and non-aggressive. These fish are usually drab in color.

Butterflyfish are a family of saltwater fish made up of over 100 distinct species. They resemble angelfish and have compressed, disk shaped bodies.

Betta Splenden fish are one of the hardiest species of freshwater aquarium fish and are an incredibly popular mainstay among hobbyists.

Scorpionfish are a family of marine fish comprised of over a 100 different species. They are counted among some of the most poisonous animals in the world.

Batfish are a family of marine fish, similar in appearance but unrelated to the angelfish. Juveniles are characterized by their bat-like side profile.

The Molly is one of the most popular species of livebearers in aquarium culture. It is a hardy and adaptable species and are great for beginner aquarists.

The foxface rabbitfish is a popular species of saltwater fish belonging to the rabbitfish family. When stressed, they can change to a mottled brown color.

Triggerfish are a fish comprised of roughly 40 distinct species. They are characterized by their laterally compressed bodies and comparatively large heads.

Grunts are a family of saltwater fish made up of 150 different sub-species, some of which have been successfully introduced to the aquarium hobby.

Catfish are a large family of freshwater fish extremely popular in the aquarium trade. Extremely hardy and make for fascinating aquarium specimens.

Often regarded as the king of the freshwater aquarium, discus fish are one of the most beautiful species of aquarium fish; and one of the hardest to keep.

Most acara cichlids are somewhat aggressive and territorial and they have a tendency to eat smaller fish. Acaras come in a wide range of colors.

Filefish are a curious species of saltwater fish. They are characterized by their rhomboid shaped bodies, thick, sandpaper-like skin and small, fleshy fins.

Snappers are generally non-aggressive fish that do well in very large saltwater community tanks. Most live in rocky or coral reefs, and come in many colors.

Danios are a popular species of freshwater fish in the aquarium hobby. They are characterized by two pairs of long barbells that hang from their mouth.

Also referred to as Rope Fish, Dragon Fish and Snake Fish, reedfish are a curious species of fish characterized by their long, snake-like bodies.

Ram Cichlids (Mikrogeophagus ramirezi) are a species of freshwater cichlid that can be found in slow-moving waters throughout the Orinoco River basin.