pinpoint PH probe

[jimsta]

how often should you replace the ph probe,and if so how do you know its time to do so.

 

[pjmoore]

I recall hearing 18 months from a couple of people. I replaced mine at approximately that. I knew it was time to replace it when after calibrating it began reading negative.

 

[jimsta]

lol...thanx

A friend asked me and I had no idea what to tell him, I figured someone on here would know the answer.