okay thanks sammy.......i kinda know what you are saying.......and i understand.....but how exactly do you know if a coral is bleaching other than the visable charateristics of it......i.e...loosing zooxanthellae algae....and lightening of the corals color.....i have a finger leather that is ligher than it used to be...but it still opens and acts normal.....same for my frog spawn.......is this normal and just an adjustment to my lights......or tank position...or is this in fact bleaching.....i donno.....