Believe it or not, BPs have been shedding and pooping on their own for quite some time now. Although it may seem to make sense on the surface, there's basically no reason to soak a healthy BP. And, doing so can actually cause them stress and do more harm than good.
During, or leading up to, the shedding process, they produce their own lubrication between the new and old skin. Soaking in water can counteract this process and actually cause shedding problems. Water is a pretty terrible lubricant when there are other natural fluids involved.
You also say that it helps "keep him regular" and he seems to enjoy his baths. How do you know? What exactly is regular for a BP? When I read that, I can only think that he is likely "stress eliminating" from trying to escape the bath.
If I were you, I'd put the time you're spending giving him a bath to better use.![]()