Yeah and your cold floor ambient air temp theory will be out the window when you dip that meter 😂
its not a theory........ambient air temperature,flow,freezing cold ground,original temp in my tank before heating and how much hose i have off the reel all affects the temp at the brush end when im using hot water...its a fact....
i do wonder what planet your on sometimes nigel!
ive been using a tds meter with a temperature button for years mate,just time to replace after 8 years and 2 lots of batteries,its finally given up the ghost.....