A little more information about your environment please: type of cage, vents, heat,....
I'm going to repost my answer to the other Question:
Humidity is water vapor and air pressure. You can have the CHE and a sealed tank and you'll get your humidity.
Your heat rising and vents positioned in the back like that draw air from the outside in, pull it through and spit it out the top. In normal room temp, if you sit a glass out, at 70 degrees it evaporates relatively quickly. You have to find your cages balance between airflow and moisture.
CHE's produce a very dry heat. I don't know why.
Close up your vents a bit. You'll see fog on the glass last longer the less airflow you have. But then this gets into health benefits of fresh air. This has been a great heated chondro debate.
I've found bowls of water are pretty useless in an open system. They don't evaporate quicker than the air flow. Therefore, humidity (since you lack pressure) drops.
Try a rolled up wet towel on one side of the cage, or a kitchen towel on the side (dunno how you'd get it there).
With arboreals, it's easy. The wet towel as a substrate provides an enormous amount of evaporation. With the damned ground dwelling fecal smearing terrestrials, it's a far bigger challenge. The rolled up towel though should provide good retention and surface area for adequate evaporation once you pressurize the system by closing the vents a bit.
Never share towels with other cages, if they get soiled throw them out. Cheap rags/dishtowels can be found at wally world.
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