I think it was just damaged at the base. Was watching it since I got a good look at the base and it looked messed up, happened to be watching when it broke off and started floating about. Last I saw of it was when my female clown gave it a nibble as it went behind the rocks.
Probably my fault. Cleaned the glass yesterday and scrapped off some baby aptasia, one may have fallen into the colony and got a good sting in. Normally don't pay attention to that since galaxia vs aptasia usually comes out with galaxia with the win.
Looked at the patch I scrapped back a bit to remind myself how many I scrapped off and saw a little baby berghia, only put in medium ones so they are reproducing. Spot is between mp10 and glass and there is not enough space for the scrapper.