ACII pH Probe Problem

[Medicine Man]

I started to notice that the pH from my AC II's probe was giving a false low reading so I recallibrated it using 7.0 and 10.0 solution. The pH started showing 5.4 and lower. I recallibrated it again and now it fails the high (10.0) portion of the calibration. It will display the 7.0 correctly but when it is inserted into the 10.0 solution it will only read about 7.4. The probe/ACII is only 4-5 months old. The pH probe is the "lab quality" probe. Thanks for any help.

 

[wakesetter]

,.

 

[cwegescheide]

This might sound a little wierd but it worked for me.

Make sure your cable to your PH probe is not all wrapped all over itself. I had a problem just like yours and I don't know if it was coinsedence but when I straightened out my cable it calibrated OK. Some sort of interference possibly?

 

[clp]

Try the following:
- If you have a serial cable unplug it, and see if the readings change. If so you have a ground loop and need to install an isolator (SERIPC9).
- Power cycle the controller (remove 9V battery and AC adapter at the same time), and then recalibrate the controller.

Email me support@neptunesys.com the values shown during calibration if you continue to have problems.

Curt

 

[Real Reefs]

How old is the calibtation fluid? I find if I use my calibtation fluid 2-3 times it looses it's accuracy.

 

[Medicine Man]

I have 2 pH monitors on my tank. One for the Calcium reactor and the other just to monitor the ph in the tank. I used the same solution for both meters and the other calibrated just fine. I will have to try the solutions mentioned above and get back with you. Thanks for the help!

 

[Leopardshark]

Something like this is happening to me, also the probe is the lab grade and itÃ"šÃ‚´s been running for about 6 months, could it be a bad batch?
Marco