No, I have avoided thinking about the damn thing for a decade.Do you check the accuracy of your pH pen from time to time? Even a brand new pen has to be calibrated before use. For me that means dipping my pen in a calibration solution sold by the manufacturer of the pen, and adjusting my pen to 7.0...
My pen:
Calibration fluid:Milwaukee pH600AQ Digital pH Pen
The Milwaukee Instruments compact pH pen tester is often used to help maintain pools and aquariums as well as improve results for growers and quality in a range of food and beverage uses.milwaukeeinstruments.com