What is happening to my chalice?

[jonny]

So I have a wonderful piece of orange kush chalice that has been doing fine in my tank for at least 4 months, I recently moved it from my frag rack an mounted it on my rockwork. Soon after its started to look a bit haggered, which the first...occurrence I guess? I assumed my urchin had accidentally munched on it (he does this to the edges of my encrusting corals every once in a while) but this is what it looks like after the 3rd time. Its not something that is happening gradually, it happens in chunks just over night. Do you guys think it the urchin, and if so, what do you think I can do to stop it?

 

[GHill762]

is it getting more light now than it was?

 

[jonny]

Its up about 3 inches higher, so yes, but not by much. I had considered bleaching, but the fact that its happening in parts over night made me doubt that..

 

[Tab28]

Looks like when i have a chalice frag that starts to melt/recede. For myself it is usually something that went wrong in water perimeter like alk, ph, salinity or something that caused damage to skin. Like what you mentioned these things always seemed to happen at night. If i was able to correct what caused it must times they healed.

 

[jonny]

I have a couple other chalices and many other corals that aren't having any issues..the first time it happened was roughly 2 weeks ago, and clear flesh has actually grown back over the spot that was bare. (Near the rim there on the front)