Did I mess up my ph probe by calibrating it?

Silly clownfish · Nov 20, 2024

Don’t fix what isn’t broken! My ph probe is at least 5 years old and hadn’t been calibrated in probably a couple of years. obviously I don’t chase numbers and my apex is mainly for watching things when I travel. Anyhow, I read something recently about calibrating every few months, so decided it wouldn’t hurt.

Prior to calibration, I had pretty, smooth charts with a nice sine wave varying from about 8.0 to 8.3. Calibration shifted my instantaneous value by about 0.04 - not enough for me to care and I suspect within the margin of error for a probe.

A day or so after calibration, I noticed that although my tank was staying in the same range, my once smooth, pretty graph is now jagged, with little .01-0.02 bounces. Not enough for me to be concerned, and as long as the tank looks good, I am happy. But I wonder - could calibrating it have messed up something with the probe? Is this normal?

Yeah, I know I should probably get a new probe, and will ask for one for Christmas and stick it in the empty spot on my apex, so rally just curious.

Johnd651 · Nov 20, 2024

Working in a lab we used to calibrate every 12 hours. You do get drift, but I don't know how apex calibrates... is it 1 point or 2?

Randy Holmes-Farley · Nov 21, 2024

Calibration does not change the probe. It changes the device attached to it.

It may need cleaning, but the bumps you note are very small and not unusual.

Silly clownfish · Nov 21, 2024

Thanks. I figured it shouldn’t have broken anything. I was surprised that the value at the time I did the calibration was so close and that it really hadn’t had drift with not being calibrated in years. It seems most people would have replaced it a couple of times by now.