My Gold stripe Maroon lived in my frogspawn and Hammer. First he live in the frogspawn. It was HUGE, over 30 heads. It was globe shaped he would actually hide inside, rather than in the polyps, but he would aggrevate the polyps as he swam out to attack passersbys and then swim back in. Over time it would extend less and less, so I fragged it and trading all the pieces off. Then he move on to live in my giant hammer coral. GRRRR!!! He eventually killed that. It took about 8 months. It would put out a few less polyps day after day as his fat a$$ layed there on it. I actually gave it to the LFS for free at the end to try to save it, but to no avail. As soon as that clown is gone in a few weeks I am getting more hammer & frogspawn.
So yes they will roost is LPS, but not so much to the benefit of the coral in my experience.
Getting clown fish= My dumbest mistake yet