Moved from here.
sorry for highjacking, but I calibrated my pH meter and I think I screwed it up cause it always reads higher than the TF pro. How are you doing regular calibration? Do you have a stock of the test powders that came with it, or are you doing it another way? I also am fighting high pH and using lots of acid, but I have new plaster so I guess that is to be expected.I have a digital pH tester that goes up to 14. I calibrate it routinely so that it's accurate to 0.01 on the scale.