i believe that would be fine and some people to put them inside their tank if they have the room. just make sure they cant come in contact with it, either just cant reach it or has the cage style gaurd on it. If nothing else, get a cardboard box as a hide/platform like i did and just put something on top of it, a piece of carpet or paper towels, etc.
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Not sure i would leave the top off tho, beardie's can jump lol