PH Probe Shot

[greenmonkey51]

Something is going on with my ph monitor. A couple days I added some alk supplement and it started showing some really high numbers for a few hours. So I recalibrated it and it was really off on the ph10 solution. I got it calibrated and today I look over and its showing the ph as 8.7. The tank normally runs about 8.0 and it was reading fine earlier today. I haven't done a thing to the tank besides a little top off. I even added that in a separate compartment than where the probe is. I'm doubting the ph shot up .7 points so quickly. Everything seems happy. The probe isn't even very old. Maybe 4 months. I just did a quick check using the ph7 solution. It read out at 7.8 for a 7.0 solution. I don't know whats going on.

[bertoni]

Hmm, what brand of monitor? Is it running on batteries? Power line interference is a fairly common problem. A probe should last longer than 4 months. Have you tried cleaning it?

[greenmonkey51]

Its an American marine, running on a Rayovac battery. I tried cleaning it a couple times.

[greenmonkey51]

I think this probe really is crapped out. I checked it this morning and its reading 10.34.

[Randy Holmes-Farley]

If you are measuring and calibrating away from the tank and any assocaited lighting ballasts, then if you cannot get it to calibrate, I'd try soaking the tip in full strength vinegar overnight. Then rinse well and recalibrate, if possible.

[greenmonkey51]

Could a low battery also be a cause for trouble.

[greenmonkey51]

Battery was the problem. Unfortunately I ran out of calibration solution. Thanks for the tip about calibrating around ballasts. Never would of known.