When I researched CHE, I discovered that the heat only penetrates approximately 14 inches. In a taller enclosure (as is mine) I set my temperature gradient from top to bottom. Use your CHE to establish the lowest temperatures in your set-up at the bottom of it. For example, in my set-up the night time temperature with only the CHE's on never dips below 65F (which is also my night-time thermostat setting during the winter). Warm air rises, so even though the bottom of the viv is 65F, the sleeping area (basking branches, tree limbs, etc.) which is approximately 2 1/2 to 3 feet above ground level is 75F. A little higher is (4 to 4 1/2 feet from the bottom is 85F.) The dragons move to adjust their body temps. When the basking spots, UVB strip light and Mercury Vapor bulb come on during the day time hours, they bump the temperature up to the 84-88F range on the limbs and branches and the bottom area elevates to about 77F. When I had my dragons in a tank, my gradient was side by side. One side cool and the other side hot. Hope this helps a little.
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dianedfisher@yahoo.com

My 3 CWD-Avanyu, Tripod and Drago