My advice, and my opinion, is if the CB is not killing it....ride it out and do NOT change anything. A lot of times making changes is much worse than letting things take their course. If he is eating it or killing it......different story. CB are not really partial to xenias in my experience, so keep him well fed and hopefully he is just tasting it to see if it is food since it is new. If it doesn't work out.....I personally would prefer a CB over xenias anyway. Any reef I have nowadays has a coral beauty in it. Just my opinion....moving the fish to another tank and back stresses the fish........moving the coral around stresses the coral....if you plan on keeping the fish......just ride it out......if he eats it....fine, you know not to buy another xenia, but if he gets bored and decides it doesn't taste all that great....super.....you have both. We put things in our tanks from all over the place........things that don't even see each other in nature.....basically fish have to taste new things because they have no idea if they are food or not.....hopefully he won't like it. Just my opinion.