zoos bleaching

[S13<3]

what causes zoos to turn clear/white? a freind of mine is having trouble with his zoos they are all bleaching slowly, i took a small colony to see if i could nurse it back to health i hope i didnt contaminate my tank

 

[Scopus Tang]

Primary reason in an aquarium is due to too much light. However corals will also bleach as a result of high temperatures.