High humidity could cause scale rot if they are sitting on wet bedding all the time.

Your ceramic bowls are too small if the snakes are knocking them over. I use ceramic souffle bowls for the smaller bps, and give the larger ones plastic dog bowls. They need to be the bowls that fan out at the bottom. This is exactly what I use, I get them for $1 at the dollar store http://www.mypetsuperstore.co.uk/ima...amine_bowl.jpg Just make sure it doesn't have the cutouts at the bottom for you to pick up, the snake can dump it over then. I like those bowls because they are big and keep my humidity up in my large tubs.