<a href=showthread.php?s=&postid=9822660#post9822660 target=_blank>Originally posted</a> by elegance coral
Those are secondary pigments. The algae within the coral are brown. If it servives it will start turning brown in spots as the algae reproduce. Desertbandits brought up a good point. If you can get it to feed it will have a much better chance of survival. It's not getting the nurishment it needs from its algae anymore.