Disease, Fragging Mistake, or Water Problem?

[krustyart]

*(see attached photo - if I can figure out how to correctly attach the darn thing!)

This Brain Coral started out as a tiny 5mm x 5mm frag I made of a friends dying coral (his tank crashed due to neglect and he gave up). I had little hope for it and mounted it in a deep crevice in a rock and forgot it for a year. I noticed from time to time that it had colored up a nice bright purple and turquoise and was growing. It now fills the crevasse that was several inches deep, up to the surface of the rock. The problem started a few weeks ago. As you can see in the pic, there is a huge, presumably liquid-filled bubble at the bottom of the coral formation. It does not pull upward as if it's full of gas so I am only assuming it's liquid filled. I am a total novice in weird stuff happening to corals. Can anyone shed some light as to what the problem is and how to fix it. (I hesitate to puncture the skin of the bubble!!!) EDIT --> yes, I know that there are bubble algae in the picture. No need to berate me there.)



Thanks in advance.
ART

 

[Epicreefer]

That coral looks a lot like a favia to me. I had one a few years back do something similar. Formed a blister/ bubble about the size of a nickel, a few weeks later it was calcified but not attached to the main skeleton. A few weeks later I cut it off, it may have been separating already, don't remember, and glued it to a frag plug. The main colony healed in a few days and the frag healed up in a week or two.

 

[krustyart]

The bubble is about 2.5" in diameter.
There is one other coral, Bubble Gum Monster chalice, that has a very similar bubble.
Could they be related or do you think it's just coincidence?

ART

 

[Crabkins]

I have four 2" pieces of Xmas Favia that are doing the same thing. The bubbles all formed in July and are water filled, calcified and on the leading edges. One bubble per piece. The corals are all growing very fast. I suspect that this is asexual reproduction and have left them alone to see what happens. I asked around and was told that is either 1) light shock (I grow outside under 80% shade cloth and it is quite bright in summer or 2) asexual repro. So take your pick, time will tell. I was going to cut them, but I'm going to leave them now. I'll post again when I have the answer!