What are reef producing coral called? what is the coral reef composed of? how are they created?

Hermatypic corals are known as reef producing coral.  A coral reef is made

up of the compound called calcium carbonate.

Hermatypic corals are also referred to as hard corals as a result of the

presence of the compound containing calcium which solidifies their body.

The coral is formed when the larvae gets attached to rock in a water body.

As they grow, they begin to secrete calcium carbonate beneath their

bodies as a result of the prolonged proximity with the rock particles found

in water.

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