Soft corals are also called Alcyonacea. They are part of the class of Anthozoa and grow branches or tree-like. Soft corals are composed of a colony of individual polyps and have no solid limestone skeleton. Most Alcyonacea species in the shallow waters of tropical seas and form a symbiotic relationship with zooxanthellae. Their color spectrum varies from brown, yellow to green. Other soft coral species prefer deeper regions and feed actively. These types often have conspicuous stains, such as bright red, orange, or violet.