I just got my two new ball pythons today and I am very excited a male pastel and a normal female. I just have one question though. Where do you place the thermometer probe directly on the glass above the UTH or on the substrate. I am useing repti bark but If i place it on top of the substrate it wont get to 90 degrees even turning the rheostat on high, but if I place it on the glass above the heat mat it will get up to 90. I just dont want to make a mistake and hurt them. Please let me know the proper placement. Thanks
Ed