Heat mat thermostat

[PitOnTheProwl]

I'm completely new here, but I have a zoo med UTH on a zoo med thermostat. With the thermostat cranked all the way up, it only got my tank to 74F right over the mat. I'm thinking my layer of sub straight might be a little too thick tho.

And you want to measure your temperatures UNDER the substrate as it will be the hottest surface your animal can touch.