Hi
Just ignore the reading on the thermostat it's only relevance is it's link with the ACTUAL surface temp in the viv / tank / rub .
I take an accurate reading of the inside surface temp under the warm hide ... and adjust the thermostat accordingly until I get the temp reading I need as I said at this stage the thermostat temp reading is irrelevant .
Plus what kind of thermometers are you using ?
Hopefully not one of these ..
These are much better at about 3 or 4 dollars off eBay ..they have the F ~C option
Also maybe consider treating yourself to a ten dollar digital heat gun off eBay / Amazon ..
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