I had elongata type xenia growing like mad once. Definitely can pull it off (to get it completely off that spot), or cut it (OK, but that jelly will grow back into another full blown stalk). Either way, find the thicker pcs with maybe 3 or 4 branches. Attach'm to rock rubbles and sell'm back to the lfs
. Mine gave me $8 per. Sold them for $25.
Xenia can get to luch IMO
/IME and crash. Mine took all my coral with it and most of the inverts. Jst too much died off and the ammonia was uncontrollable I guess. My thoughts are that if it gets too thick and not allow water flow between the stalks, you'l get in trouble. I've read that described as chocking in its own mucous. Also, I've heard if you trim too much at one time to run carbon for a bit to absorb stuff cut xenia releases.
Garf.org has some decent reading on xenia propogation if you're interested.