Calibrating Neptune Systems Standard PH Probe

[jermahin]

When calibrating the Neptune Systems standard PH Probe with my Apex Jr it states "Place pH probe in calibration solution and wait for number at of bottom of this window to settle". How do you know when it has settled. Does the word "settling" at the bottom change to "settled". I've let the probe sit in the solution for 15 minutes and it never changes, however about every 2 minutes or so the number generally goes down 1 degree. I never know when to give up and consider it settled.

Thanks

[thor109]

It should not take more than a minute, move the probe around a little bit and wait for numbers to stabilize. Just until the don't change every few seconds.

[jermahin]

Thanks, that helped