Rays are a large group of fish closely related to sharks. Ray fish are characterized by their flat bodies and a tough, elastic skeleton made of cartilage.

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.

Squirrelfish are a family of ray-finned saltwater fish. They are characterized by their large eyes and long, sharp dorsal spines.

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

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.

Grouper are a large family of saltwater fish characterized by their stout bodies and over-sized mouths. They are hardy, colorful and fascinating species.

Pacu fish are a large family of freshwater fish related to the piranha. While some species look like piranhas, they are herbivores and are peaceful fish.

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.

Seahorses are characterized by their equine appearance. Its upper body is shaped like the head of a horse and its lower body ends in an elongated tail.

The glass fish is a fascinating species of aquarium fish. Its most astounding feature is its transparent body which reveals its bones and internal organs.

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

Cardinalfish are a large family of saltwater fish made up of over 200 sub-species. Most species are extremely colorful and are a couple of inches in length.

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

Lionfish are a species of fish belonging to the scorpionfish family. They are known for their bright colorations, flowing fins and venomous tentacles.

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.

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

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.

Archerfish are one of the most fascinating species of brackish water aquarium fish. They get their names from shooting insects with powerful jets of water.

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.

Gourami are a relatively hardy species of freshwater aquarium fish and are thus suitable for most intermediate aquarists. Square shaped, compressed body.

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

Compared to other Lake Malawi cichlids, Peacock cichlids are relatively peaceful. They come in a wide variety of bright colors, often in iridescent shades.

Parrotfish are a marine fish with over 90 distinct species. They are characterized by their parrot-like beaks that are made of tightly compressed teeth.

Saltwater eels are one of the most fascinating and demanding species of fish kept by aquarists. They are characterized by their long, snake like bodies.

Barbs are a large family of freshwater fish that are a popular choice in the aquarium hobby. Different species of barbs come in a dazzling array of colors.

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

Pufferfish are a large family of saltwater fish. It can fill its elastic stomach with water until it expands to a large, almost globe-like shape.

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.

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.

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