I have an inline Milwaukee MC 122 PH meter that drifts more acidic in its readings every day. I can verify false results with a handheld PH meter that I can recalibrate easily minutes before the test and I can do a liquid API test which shows the color and indicates that the milwaukee is indeed wrong and also needs recalibration. This seems odd as this is the trigger for a CO2
system and I've seen others who use them and I doubt tear down their system to recalibrate it every week. Whats the deal with mine? Would algae on the node cause the readings to constantly, steadily, be wrong as the week goes on?