hi andres, the bigger your temp gradient the better. there are manymanymany ways to acheive this.
any heating elament should be controlled via a thermostat, this will prevent burns.
kings do great at 60-75 cool side and 80-95 warm side. if i read your post right a constant 85 or higher during day and your drops at nite may very well stress your king, they(kings) need to be provided with a constant temp gradient availible at all times for optimal health. good luck and have fun.
,,,,,,,,,,,thomas davis

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