If you're combining a ceramic heater with a screen-top cage, make sure you keep an eye on the humidity within the enclosure. You can also head off any humidity issues by providing a moist box for your snake - i.e. a rubbermaid/tupperware container with a hole cut in the side or top, and filled with damp (think wrung-out washcloth) sphagnum moss. That way your snake has access to a humid hide just in case...

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