PH probe life?

[StrategicReef]

How often should Pinpoint probes be replaced..
I used mine for 2 years and still going. Maybe need calibration but the PH has always made sense to me.

If calibrated, can it go 4 to 6 years?

[Randy Holmes-Farley]

Some can. I usually break mine before that. :D

Things that go wrong include crud on the glass bulb that won't come off, and leaking out of the internal fluid. The latter is better with a double junction electrode, and may be better with more expensive ones vs cheaper ones (both being double junction).