pH probe question

[beaker77]

I have a Hanna Checker pH probe that I think is broke. If I calibrate it then recheck it a few minutes later the probe is between .05 and .5 off. Anyone know what my problem is? Or should I just get a different probe? Any recommendations on brand or model?

Thanks

[TWINPEAKS]

did you try new batteries?

[DrBDC]

I had one of those too and it did the same thing. I returned it and they sent me a new one that was just as bad.

[beaker77]

So would the Pinpoint pH monitor be the way to go? It would be great to have something like that mounted in my sump.

[TimBob]

I'm not sure any of them are worth their price. I am now on my 2nd Milwaukee pH meter and it started messing up the other day. The readings have been creeping higher on a daily basis. Yesterday the meter was reading 8.6 so I quickly tested with a SeaChem test kit and the pH was right at about 8.2-3.

I tried to calibrate the meter last night and I could not adjust the reading all the way up to 10.0, so something is obviously screwed up. I have a spare probe that I am going to try out once I get new calibration fluid (just to be sure)

The first meter went the other way, down, when it failed. Even with a new probe I couldn't calibrate the thing to read higher than 5.6 when the probe was in my tank.

I don't think the Pinpoints are any better, my friend has been through two of them in the same amount of time.

Next step will be an AquaController mounted outside my stand.

[SSTG]

timbob, try soaking probe in vinegar then recalibrate.I've had a pronto for about six years no problems but vary costly.

[Zephrant]

I talked to Milwaukee customer service (very helpful by the way) when I had that issue last year. I could not calibrate to 10.0.

He suggested dropping the probe in Windex. If it does not immediately peg to 14+, then the probe has gone bad, and needs to be replaced.

In my case, it could not get up to 10.0 even.

Figure about 9 months max out of a probe.

Zeph