pH reading way low after probe cleaned

TWYOUNG · Jan 13, 2023

I had to replace my Apex necessitating a reinstallation and calibration of my pH probe. Since it had stuff growing on it I cleaned it by soaking in sodium citrate. Since installing it has been reading in the mid 7's when it previously was 8.1 to 8.4. I've calibrated it twice. This morning it read 7.5 while my Hanna was 8.3. Did cleaning it cause this issue?

blaxsun · Jan 13, 2023

When you recalibrated, did you float the packet of calibration fluid?

TWYOUNG · Jan 13, 2023

blaxsun said:
When you recalibrated, did you float the packet of calibration fluid?

Temperature acclimated yes. At first I thought the acidic cleaning solution could have caused a temporary lowering of the probes reading but it's been several days now.

blaxsun · Jan 13, 2023

TWYOUNG said:
Temperature acclimated yes. At first I thought the acidic cleaning solution could have caused a temporary lowering of the probes reading but it's been several days now.

I don't know if this will work for the pH probe, but when I had an issue with my salinity probe - I performed these actions (per Neptune):

1. Disable the pH probe and then unplug it.
2. Reboot the Apex (with the pH probe still unplugged).
3. When you can log back in, reconnect the pH probe.
4. Re-enable the pH probe.
5. Recalibrate.

TWYOUNG · Jan 14, 2023

blaxsun said:
I don't know if this will work for the pH probe, but when I had an issue with my salinity probe - I performed these actions (per Neptune):

1. Disable the pH probe and then unplug it.
2. Reboot the Apex (with the pH probe still unplugged).
3. When you can log back in, reconnect the pH probe.
4. Re-enable the pH probe.
5. Recalibrate.

What do you mean by, "disable the pH probe"? How do I do that?