Types of Corals Found at Reefs

Scleractinia Coral

• Scleractinia are hard corals that grow in shallow tropical waters and can live as a single polyp or as a colony. Colonies are held together by the polyp's excreted calcium carbonate. One of the most familiar Scleractinia species is brain coral, which forms into a rounded mass with lines on the outside that look like the human brain. Because Scleratinia corals build the majority of reefs, they are the most common. Other familiar Scleratinians include staghorn coral, shelf coral and elk coral.

Millepora Coral

• Watch out for these corals. The Millepora group consists of the fire coral, which takes a variety of shapes, including stick formations, branch formations and even those that resemble underwater plants. Fire corals are covered in nematocysts that cause a painful sting if a snorkeler or diver brushes against them.

Tubipora

• The Tubipora genus has only one species, Tubipora musica. The coral gets its name from its tube-like shape. When grouped together, the coral resembles a pipe organ, and its common name is pipe organ coral or organ pipe coral. This coral is usually red and found mainly in the Indian Ocean.

Heliopora Species

• Heliopora is known as blue coral because of its blue exoskeleton. This branching coral grows well in aquariums, but it is native to the Indian Ocean. The prefix "helio" means sun and is an appropriate name for this coral because it requires strong sunlight to thrive.