So, I'm setting up my snake rack. I've never had to use a rack before, as I have never had many snakes at once before. I'm using sterilite tubs and will be leaving the lids on. Anyway, my question is, is it necessary to drill holes in the tub or is the gap between the lid and tub enough? I would think that, with the idea of keeping humidity up, you wouldn't want any extra holes. After all even when snakes are shipped the boxes don't always come with holes in them.