I have a Zoo Med Repti Therm U.T.H. that I am using under my glass tank. I am setting it up in preparation for when I get a boa to make sure my temperatures and humidity is good. I recently put some Repti Bark for my substrate and when I did, the under tank heater caused a lot of condensation on the lower part of the tank where the bark is. The instructions for the heater stress that you can't get water on the tank or it will cause a stress crack. Does anyone know if the condensation is enough to cause this to happen. I'm not sure how much water is a problem. Thanks.