Among the red green and brown algae, which is likely to be found in the deepest waters

							
Red algae is mostly likely to be found in deep water. This has to do with the different wavelengths of light and how deep they can penetrate water. Red light has the longest wavelength of the visible spectrum which means it penetrates water the least.
						

							
IN the deepest region of water, the blue-green light have short wavelength light can penetrate through,
 Red algae has a component called as phycoerythrin which helps in absorption of short wavelengths of light, thereby allowing red algae to grow in this region.
						

							
Red algae is found in the deepest parts 
 
Since they can absorb blue light, red algae can live in much deeper water where light of long wavelengths -- like red -- can't reach. 
						

							
dear friend
Among the green. red and brown algae Red Algae is likely to be found in deepest water because of a pigment present in them which is called phycoerythrin due to which it is able to absorb light of blue color and reflects red color
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