Hi i had a dumb question about the PH pen calibration. Is it actually required to Ph the pen if it always sits in the PH7 solution that I change out once a week? If the pen reads 7.0-7.1 each time I fire it up should it not be good?
Storage solution is for storing it. Don't store it in calibration solution. Just because it reads right with one solution doesn't mean it will calibrate correctly.
If you store in ph7 calibration solution it's probably been contaminated and is no longer ph 7.0.
I never put anything in the bottle of calibration solution, I pour out a small amount to calibrate.