I know my Butterflys and Angel like Zoa polyps as I feed them these if they go on hunger strike and the Angel loves them also. I have some Xenia, which grows like a weed in my reef tank, and put a large rock covered with it in my FOWLR and they don't touch it (wish they would!). I also have several rocks covered with GSP in my FOWLR which was doing great for about 3 months. Then about the same time I added a pair of Golden Butterflys it no longer opens yet I haven't seen them nipping at it! I've just put one of the GSP covered rocks in my reef tank to see if it comes back to life!
I've got 4 x 72" VHO lights which should be OK for something like GSP, mushrooms, leathers, etc. I'm not planning to add any hard corals.