Yeah, the bottoms have a shallow layer of water in them (about 3/4 inch). On mine, I run heat tape under the bottom during the day to increase humidity, letting it cool down a bit and dry up at night. Green Tree Python keepers/breeders argue about whether water is proper or not (instead of mulch or a similar product), but the best of the best emerald keepers use water as a substrate, so that's what I have under my emeralds. It's clean, easy, no smell, no mess. Emeralds don't defecate very often, and I only end up cleaning the bin less than once a month because of that. I do water swaps weekly just to freshen it up and refill. My biggest problem is the occasional blood in it after a good meal LOL. I use newspaper or paper towels under my green tree pythons since they are alot messier, it makes the cleaning easy.

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Tyler Stewart
Las Vegas NV
www.BLUEBEASTREPTILE.com