You just have to mess with it to get it right. Not much else you can do. I personally do not like going so big, either ya have to heat the hell out of it or ya can't get them warm enough.

It's always nice to think big, but in captivity I keep them a bit smaller 40 breeder critter cages. So I can only say get your temp gun and just play around with different bulbs /watts and see if you can get it right. Best wishes with it, lol.

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Eve
Suncharmers Colorful Collareds & More