My clown gets to be a pain every now and then when I rearrange the tank, if I do not provide some cover for him to hide. I would suggest trying to incorporate more natural habitat into the tank to put it at ease. I found some african bog-wood that can be kind of piled/organized to look like a underwater root system. Aesthetics aside, this provides a lot of hiding places for the fish to relax. Great looking CK by the way.