Google it & do a little research on how to frag zoanthids. It's not hard to do. Also read about the palytoxin that they have because in some species it can be quite dangerous so you just need to be aware of it & take the appropriate precautions. Not a big deal if you handle them safely, though. Are you able to take the while rock out of your tank? If so, I would think your lfs would have no problem trading you another rock of equal size with no corals on it.
I really don't see why you are so bothered about 1 adult polyp that is growing well & having babies. This is what the rest of us want, lol.
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