Frostbite Clownfish in a Reef Tank.

Most species of clownfish are orange, red, or yellow. They often have white or black markings along the body, or a combination of these colors. The common clownfish is orange with white stripes outlined with a thin black line. The largest clownfish grow from 4 to 6.5 inches long. Clownfish have many features in common with other fish. All fish have a backbone, which supports the body. A fish’s body is covered with scales bony plates that protect the body. Fish also have other body parts that help them live in the water.