I've got temp gauages in various locations in the enclosures and use a laser temp meter also so monitoring is not an issue. As for the size, the female in the lower enclosure is 1009 grams and has been in there since she was a little over 600 grams with no issues. I have several hides in each with the various temps so they can pick the spot they like. The male ia little over 200 grams so I may slip a divider in there if he doesnt adjust like she did.