The other thing to remember about humidity is that what we're talking about is *relative* humidity, which means the amount of moisture relative to how much the air can "hold" at a given temperature. So if the temperature goes up, the relative humidity goes down unless you somehow add more moisture to the air. Deep substrate is one source for more moisture; a sponge or handful of moss or some other wicking material in a bowl of water is another possible source. A water bowl is also a source, it just won't evaporate as fast as if it has some wicking material in it to effectively increase the surface area. Live plants with soil are another possible source. Misting is a possible source, but relying on that is difficult because that produces a lot of droplets that all evaporate right away and then they're gone, so the humidity spikes and then drops off quickly. Those other things I mentioned will release moisture more gradually, so the humidity will be more stable.

It's not that hard to make a glass tank work. You just have to limit how fast the moisture escapes and make sure there's enough moisture inside that can evaporate over time without making the snake sit around in a damp/moldy environment.


*Technically it's not actually the air "holding" moisture, but it's a good enough description for these purposes. Read Wikipedia for more info if you care.