[Treef]

I bought a few polyps of zoa's a while back and they are beginning to spread across the rock i have them on but recently a Ricordea began to grow out of the same rock and has begun to grow large enough to push against the zoa's and even cover a polyp or two. Is there anyway of removing the ric from the rock, and not kill it? I was told that I could just cut it off at the base but wouldn't the ric just grow back from the base? I cant break the rock either because it is at the bottom of a pile.