Subsection 11.2.2 Coral Reef
Coral reefs are built by colonies of small organisms called coral polyps. Coral reefs are found in shallow and clear waters in tropical and subtropical regions around the world. Coral reefs are composed of "reef" limestone which is formed from the accumulation of the calcium carbonate skeletons of coral polyps. Over time, the accumulation of these skeletons forms the hard, rocky structure of the reef.