I didn't mean to imply using the highest end of the range for incubation..eggs will do just fine in 68-78F and hatch. Adults will live find in those ranges too.

TO be clear, It is good to keep the adults under 80F though a few brief exposures of 85F is fine, as long as the cage has cool areas to escape that heat. Personally I use no additional heat with my crested geckos or eggs, just the room temperature of my apartment..which tends to remain around 75F year around.
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PHLdyPayne