What kind of substrate do you have? I use Reptichip coconut husk, it's amazing stuff. I usually take my snakes out of their tubs twice a week and sort through the substrate for waste and dead mice if they didn't eat. Then I'll use a two gallon pump sprayer and spray it down while I'm turning it with my hand (with gloves on). That Reptichip can hold a lot of water and not really get wet, it soaks it up instantly like a sponge, unlike aspen or cypress or any other wood based substrate. My humidity spikes and then over the course of 2-3 days falls back down in this desert climate. I try to keep it from falling too low with my ball pythons. If it does fall quicker than the other tubs I'll add more substrate and that will hold more water and hold the humidity longer. I'm pretty sure my humidity spikes to 100% when I first spray them down and I don't have any issues. I tried misting the snakes directly when I started but I had one snake in particular that didn't' like it and I think it made him mean LOL. Now I totally remove the snake, which I think helps calm down all the snakes. I think all snakes should be held at least twice a week to mellow them out.