The 84 im gettin from my Qooltek that I cut a hole in my tub its higher on the tub as to account for warm side ambient temps. I had my analog zoo med dual thermo/humidity gauge sitting next to Qooltek on substrate bed as it read a couple degrees warmer than the Qooltek. When I get home I will attempt to peel back my UTH enough to get Thermostat probe in between it. Im assuming if I get it peeled back enough to get the probe fully under it and then foil tape it fully enclosed it will be fine ? Just for perspective I lowered my thermostat last night before bed to 92 as I wouldnt sleep well if I had my Jump Start set to 104 . I woke up this morning to 62 % humidity ( I know I still need more holes) and my temp on Qooltek was 80.0. I will be receiving my AcuRite tomorrow for inside under substrate temps. Again thanks ahead of time for any and all opinions / help.