Hard Coral

hard corals, also called stony corals, are marine corals that generate a hard skeleton.

Hard corals are the primary reef-building corals. Colonial hard corals consisting of hundreds to hundreds of thousands of individual polyps are cemented together by the calcium carbonate 'skeletons' they secrete. Living coral grow on top of the skeletons of their dead predecessors. A layer of tissue covers the skeleton and connects coral polyps, allowing for distribution of nutrients as well as communication amongst individuals of the colony. Hard corals that form reefs are called hermatypic coral.

Coral Polyp Hard Coral Soft Coral