Sea fans are a form of gorgonian soft corals that rely on the current for a continuous supply of food. They may grow up to several feet across, and are most likely to be found where the current is strong. As the name suggests, they are broad and flat, and invariably face the current so as to filter the most planktonic food. Most soft corals are colored green, yellow, or brown, due to the presence of single-celled algae within their tissue.