Common Sea Fan

Usually purple but can vary to its less common colors of yellow-orange, yellow, and brown. In some cases, the color of the sea fan is a result of the environment and the chemicals in the enviroment. The principle pigments of the sea fan are fixed in the spicules (needle-like parts of solid calcium carbonate). Colors result from chemical pigments produced in the spicules. Common sea fans grow attached to the seabed and look like exotic plants. Unlike soft corals, they have a supporting skeleton that provides a framework and allows them to grow quite large. It is made mainly of a flexible, horny material called gorgonin and consists of a rod that extends down the inside of all except the smallest branches. In the common sea fan, the branches are mostly in one plane and form a mesh that is aligned at right angles to the prevailing current. This increases the amount of planktonic food brought within reach of the polyps, which are arranged all around the branches.