Take Vaughn's suggestion of the newspaper trick. It's really a simple thing but amazingly handy to settle in a nervous snake. The process of constriction and swallowing a whole prey item is a very vulnerable time for a snake so if they aren't feeling completely secure they just won't settle in and hunt/eat properly. Here's a couple of pictures of one of our tubs set up with the newspaper (and yes there is a snake in that tub lol)....

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