Hi, I was really having trouble keeping the humidity up in my rack system with the ventilation holes I put in (and I didn't even put many in), so I covered them up with tape. To my surprise, the humidity is still in the 40% range. The space between the tub and the shelf is about 1mm (very small), and I have the water dishes at the back over the heat source too. I never had humidity issues before when I used lids so I'm wondering what could be causing the issue. I can't completely seal the containers or they'll suffocate! Any ideas? Maybe I will be forever misting....