pH Probe calibration

[ReefLurker]

I am unable to locate previous posts on where the pH reading from a probe is routinely lower then when other methods of testing pH are used. Would someone be able to supply me with the differences they have experienced with comparing the values from a probe vs strips or reagants?

Has it ever been determined as to why the probes generally show lower pH values?

Thanks,
Jeff

[kenargo]

Many PH strips tend to read high; meaning that the real PH in the tank is less than what the strip shows. Trust the PH probe, especially one recently calibrated.

[treefer]

ahhhh, anybody know the general average slack inbetween the probes and the test kits