Thermostat + heat tape, bubble wrap

[KMG]

I am now concerned about the hot spot...
I am using a paper towel as substrate. I just started running my set up couple hours ago, and thermostat is set at 96.
My concern is that, when I use temp gun to measure hot spot, below the paper towel, I read about 91 degrees. When I measure on the paper towel, it gives me 82. Am I suppose to make the temp above the paper towel 90~ish? because I heard someone saying that I need to measure below the substrate. Also, I don't even know if I am measuring proper temp of under paper towel because it is a tub and visible through. I can see heat tape and when I point my gun at that thing, I feel like it is measuring the heat tape, not the floor temperature.

You're killing me smalls. I answered this in the other thread.