Algae
In our waters, plants and algae are found only in shallow water where sufficient light can penetrate for photosynthesis. It would be unusual to find algae below 10-20 ft, so our wrecks and reefs, despite the profusion of attached organisms, are actually devoid of plant life! Of course, that is completely neglecting the microscopic algal plankton that is so profuse in our waters and so lacking in the clear water of the tropics.
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