Funny, (well not really) I bought electrode storage solution and electrode cleaning solution with the meters, but haven't used either yet. You might try cleaning with a good part A and B solution. You dip it in A, then B, then A again, for 5 minutes each, then rinse well. Or, you might consider storing it in neutral calibration fluid (7) for a while, and see if that'll bring it around. Then 4 probably would stop working.
Opie Yutts Reviewed by Opie Yutts on . Rhizome/Opie/Anyone who uses Truncheon PH Meter Help!!! I can't get mine to calibrate lately! I've tried cleaning the probe, and even changing the contact ring (only had it about a month....:() but I keep getting that flashing green 5. It calibrates to the 4.0 solution I have (made by BlueLab) but not the 7 (made by Hanna) although it DID calibrate to the hanna solution previousyly. Any tips? I use new solution each time and check it once a week, keep the cap with 4.0 solution damp on the sponge and rinse the probe each time I use it. HELP!! Rating: 5