A coral reef is a type of biotic reef that develops in tropical waters by the growth of coralline algae, hermatypic corals, and other marine organisms.
Coral reefs are typically massive biogenic formations of calcium carbonate (limestone) that is deposited within or around the bodies of the inhabitants of the reef as skeletal material.
This material gradually accumulates as debris and/or is knitted together by the continued growth of the attached forms living on the reef..
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