Red & Purple Algae
Red algae actually vary in color from straw-yellow to deep-purple or black in appearance.
Agardh's Red Weed - Agardhiella subulata is very common and grows in tufts and clumps to about 12" in sunny shallow areas.
Laver or Porphyra ( above ) is similar to Ulva in many ways, although unrelated. It grows interspersed with Ulva in shallow sunny areas, and like Ulva, it is edible.
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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