Humidity problem, help!

[Coluber42]

Reduce the amount of ventilation. If you have a screen top, cover it over completely with foil, saran wrap, plexiglass, wood, etc, and then make whatever small air holes you need to get the humidity to stabilize. If you're using a heat lamp of any sort, obviously leave an opening in the covering for the lamp (then you will not need any additional holes).

You can use a larger water bowl or multiple bowls, or damp sphagnum moss, or a shallow dish of water with a sponge or washcloth sitting in it to help increase evaporation. Some substrates also retain moisture better than others. But the first thing to do is to limit the amount of air that is lost to the outside.

Also, make sure you have a digital hygrometer (a household indoor/outdoor thermometer that you can buy anywhere) , not a cheap dial one, or you'll never know for sure.