Question

Which of the algae is responsible for the red colour of the red sea?

Answer 1

trichodesmium erithrium

Answer 2

Occasionally, the sea becomes filled with blooms of cyanobacteria algae, called trichodesmium erythraeum, which, upon dying, turn the usually blue-green water, reddish-brown. The color is not intense and is said to vary across the expansive body of water.

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