question on pH probes

[ctreefer]

I have a milwaukee pen style pH meter (sharp ph51) and I'm not sure how I'm supposed to store the meter (probe) when not in use. The directions say to add a few drops of storage or ph 7 solution to the cap before putting it away. I tend not to check pH very often (months sometimes) and everytime I pull out the meter the probe is dry and way out of calibration and it takes hours to get the probe back calibrated. Those few drops don't seem to cut it. Maybe this means I need a new probe as its been about 2 years probably. Does anyone store the probe in a full solution to keep it wet at all times? How often do you calibrate and is it common for the meter reading to fluctuate wildly while holding it in your hands to check a reading?

[mrongi1]

pH meters generally have 5 solutions:

4.0, 7.0, and 10.0 solutions are used for calibration. Only use the 2 within the pH you are testing 4 though so 7.0 and 10.0.

Then there is a separate buffer for storage which is usually between 7.0-8.0. The 7.0 calibration buffer is your best bet to use. The electrode at the bottom needs to fully wet at all times so never dry it off. Use a container with a cap and cut a hole in the cap so that the probe can slide through the hole and fill the container with 7.0. There should also be fluid inside the probe at all times, which is a special buffer.

pH meters need to be calibrated every time they are used. If your electrode has dried, chuck it and get a new one. Even the probes that are mounted inside the tank need to be calibrated on a regular basis. And no, the pH should not fluctuate wildly while taking readings. It should steadily move. Make sure your not holding it by a powerhead or water outlet of some sort, but even that shouldn't make it go crazy. If not sure of the one you have but calibration should take about a min or 2, not hours. It sounds like yours has went bad, I would get a new one.