Don't cross your fingers, it makes it very difficult to move things when you do that.Pick an area where he will get a moderate amount of flow and ample light. Then be prepared to move your coral should he go somewhere else. Short term exposure (like when he's moving around) shouldn't be a problem. It's the long term effect on some corals. I don't mind if mine takes up residence on a sheet of zoas cause they will grow in the direction the anenome isn't. But I've had long term damage done to a SPS piece or two over a week or so of exposure.Not sure if I'd be too happy if mine took up house on a rock that housed permanent sps. If that becomes an issue I'd move the rock around so that it's no longer pleasant for him. He will move.