Last night, I noticed this bubble forming in my caulastrea. As I watched, the coral quickly deflated shooting out a big white cloud. I thought maybe it was spawning, however the bubble remained. As I watched longer, it re-inflated and eventually the mouth stretched wide enough to reveal the bubble was actually a big air bubble. Finally the bubble floated away leaving a healthy looking, inflated polyp. I believe that the reason for this, was excess O2 production, due to excess lighting. It is strange however, because the coral has been there for over a month and this polyp gets the least light of any of them. Also, the lighting isn't that intense, 4x65W PC's and the coral is less than mid-level.
The bubble begins
here is the visible air bubble
Now it's gone.
Full tank
The bubble begins



here is the visible air bubble

Now it's gone.

Full tank
