Acro coral turning green and dye over night

[Bblinks]

Every time I do a water change or when the coral is out of the water for a bit it will usually produce slime coat. I think you need to check your parameters and make sure everything is in line first then start looking for other possibilities. Would it be too much to ask for a picture? Most of the time when a coral is in good health, it will produce slime coat when it gets stressed out and if it is ****ed off already the extra stress will simply put it over the edge.