Ive got a heating pad on high, no substraight, just to see how hot the bottom would get righ tover the heating pad.Im using a digital hydrometer/thermometer put the sensor right on the plastic. I took the heating pad out of the cloth sleeve it comes in, in order to get more heat and the highest reading I get is 88.3 degrees. Any ideas what I should do? Repti-therm maybe?