Plate coral problem

[Hens4Fish]

Hi All,
Quick question. I have a short tentacle purple plate coral in my 150. I have had him for about 5 weeks and he always looked fine. Today he did not expand at all, which was fine, but now tonight he is blowing up like a ballon. Has anyone ever had this problem? His tentacles are not extended, but his whole body is huge. My params are fine and everything else looks great. Just wondered if anyone had this issue before.
Thanks,
Bill

[ADA33]

Mine usually will blow up like a balloon at night. One thing I read is that it will do that to get the sand off it.
I think it is fine.

[LBCBJ]

Sounds normal. Mine does it every so often

[Salty Brother]

Mine will sometimes inflate a little. But I had my frogspawn fall on it once and it puffed up huge, so maybe it was irritated by a coral. But I bet its nothing.