Algae to form coral reefs.
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fire
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red

RED algae help to form coral reefs.

Red algae contains the pigment phycoerythrin which gives out the red color of the algae; it absorbs blue light and reflects red light.

The Red algae that help to form coral reefs is the coralline algae. The coralline algae secretes a hard shell of carbonate around themselves, which in turn becomes a part of the coral reefs.

It will dry out with less sunlight