I have witnessed my bubbletips, mostly my mother bubbletip split many times. I have actually watched it squeeze itself through
live rock not worrying that it was so tight a spot that it tore itself. The result was a a little pico bubble very fray lookign that was less than an inch wide. I gave it to a local reefer and he recently told me it is huge and I can tell from his pictures that it is now at least eight inches wide. If you feed them regularly they will grow larger than you would think. I tend to stop feeding when they get too big for the surroungding corals. However I have never had a coral stung and I have watched my bubbletips flapping into corals regularly. Not recommended to let happen(you never know).
Anyway long story short as usual, it is very possible you have a mini bubbletip hiding in the rock. I have two splits recently that are an inch and literally 1/2 inch. The cutest bubbletips I have ever seen. I have recently seen pictures of bubbletips in the wild that get damaged into many pieces by falling rocks and these pieces are known to generate in the wild and I am talking about some mangled pieces.
I have given the other large ones away to local reefers and have my mother bubble still along with the two pico bubbles.
Keep your eye out. I did not know for two weeks that this little 1/2 bubble was hiding in my 30g cube.
