Hi, I noticed in your last post today that you said that the top is 73f and the matts are set at 75f and that this is close to there natural environment. They bury to cool off during the day and to absorb moisture from the earth (soil) and to stay away from daytime predators, so being warmer underneath isn't very natural. This is why they come out at night when the temps drop in the wild. And during the day outside even though the sun is beating down at the ground you would be surprised at the actual difference in temperature from the surface of the ground to even an inch down. We had a heat wave here this summer and I took my infrared thermometer outside to conduct an experiment that I actually posted on here, and there was like 15 to 20 degree difference. So not saying to take your matts off the bottom if this is the only way to get his temps right and keep him healthy, just if your really trying to mimic his natural environment he shouldn't have heat comeing from underneath him. Again I'm not saying to remove your matts because I understand some people just don't have another choice.