I'm not sure if you'd want to do that as the heat has to go somewhere. Boxing it off will only allow the heat to leave through the water. I know the casing isn't the best in transferring heat, but there still is some heat transfer. Make sure you have your computer setup to shutdown if the pump dies or turns off. I saw someone's aftermath of a pump failure and it wasn't pretty. Basically had melted the o-rings, causing water to leak all over.