Yeah set it lower. Are you using the mat stat or the pulse stat, the pulse stats like I said are much better then on off, I have 4 american pulse stats and love them since my temp stays steady instead of 87 then 90 then 87 then 90, could be stressful on snake? That's one of the reasons I say to put the thermostat probe under tub bc of the heat that gets trapped, since there is no heat getting trapped where the tub isn't sitting its going to vary, plus you have air that's cooler then the mat hitting the top of the probe since its not under the tub. Just set it lower and see what happens.

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