Discolouration on bubble coral
Hi, I have had a 55l reef tank with a bicolour blenny.
Yesterday I noticed a white colour that looked like frost on the top of part of my bubble coral. I have no idear what it is can you help? I have had the coral for about 2 months and it has being doing fine. I have some harder corals to look after and they are fine, this includes a red bubble tip anemone, so doubt it is water quality as the bubble coral is hardier than my other corals. Any help is on what this is is much appreciated. Thanks for reading.