ok i have a 55gallon tank and i have had a he!! of a time getting the humidity to stay up. between spraying every few hours to moving water bowl directly under heat. i could never seem to keep any kind of raised humidity in the tank. so last night i got some of the press and seal wrap and i put it across the whole top of the screen and put the lights right on top of it. the wrap hasn't had any probs with the heat and the humidity after a few sprays is up and holding around 70.