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

Dragonets are a family of small, vibrantly colored saltwater fish. There are over 130 species of dragonets identified and similar in appearance to gobies.

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.

Freshwater hatchetfish are a type of ray-finned fishes belonging to the family Gasteropelecidae. There are three genera, with nine different species.

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

The species known as frogfish are all members of the family Antennariidae which is sometimes known as the anglerfish family, especially in Australia.

The Neon tetra is an incredibly beautiful species of tropical freshwater aquarium fish. Neon tetras usually grow up to around 1.2 inches in length.

Knifefish are a fascinating species of freshwater fish belonging to the eel family. They are characterized by their long, tapered bodies and anal fins.

The Plecostomus is a type of armored catfish that is found throughout the tropical regions of northeastern South America.

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

Oscars are one of the most popular species of freshwater fish in the aquarium hobby today. They are also a highly intelligent species of fish.

Jawfish are species of saltwater fish very similar in appearance to blennies. They are characterized by their comparatively larger mouths and heads.

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.

Lake Victoria cichlids are fairly aggressive fish. These cichlids are some of the most vibrantly colored freshwater fishes in the world.

Sweetlips are a species of fish belonging to the grunt family. They are characterized by their big, luscious lips and come in a variety of colorations.

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.

Known as trunkfish, cowfish and cofferfish; boxfish are a family of bony marine fish. They are known for their square shaped body and heavy armored scales.

One of the most commonly available species of freshwater aquarium fish, the guppy is a long favorite amongst aquarium enthusiasts worldwide.

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.

Silver dollars are an extremely popular species of freshwater fish. They get their name from their almost round shaped bodies and silver coloring.

The flounder is also known as a flatfish; a fitting name because its body is laterally compressed and it lays on its side, burrowing into the substrate.

Paradise fish are a colorful species of freshwater fish belonging to the gourami family. They were the first tropical fish to be imported 150 years ago.

Mbuna cichlids are some of the most brightly colored freshwater fishes in the world, exhibiting a wide range of colors and patterns.

Species belonging to the genus Naso are typically referred to as unicornfish because they have a long pointed protuberance in the middle of their heads.

New World Cichlids are some of the most diverse freshwater fish species in the world. The colors and patterns of New World Cichlids are highly varied.

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.

Also known as cories or cory catfish, Corydoras catfish are bottom feeders and generally docile fish that do well in a community setting.

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.

Dartfish are a family of small, colorful saltwater fish. They are similar in appearance to gobies and are characterized by their long, eel-like bodies.

The ray fish''s skeleton is made up entirely of cartilage and it is characterized by its flattened body and large pectoral fins which are fused to its head.