He can go up to 3 weeks without eating, and without much concern. The 12x12x18 is probably fine for that size, but you may want to add an extra feeding station or two. He is perfectly normal.
You won't see him move much, if at all, during the daylight hours. He will find a favorite spot and look like he always stays there, but he will move around at night while you are sleeping.
I would advise a digital thermometer/hygrometer when you have a chance. Those little stick-on things aren't very accurate, but are better than nothing.
Eileen
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