Ozzy and Widget are set up on a twin channel stat. For a while now the thermometers for both of them have been giving of low readings. Ozzy about 22-23'C and Widget about 23-24'C. I have turned the stat up but it hasnt made any difference. There mats do feel hot to the touch but not as hot at Hiss's which is at 29'C according to his thermometer.
Using digital thermometers. The probes for the thermometers and the stat are tied together with a cable tie and are positioned in the hot end of the tank.