How often do you calibrate your meter?

I figured one would get me thru a cycle (this one has been in the process since nov 2nd so it is an exception). I started 12/12 16 days ago and noticed some phosphorus and potassium deficiencies right around the time I flipped. Thinking she needed more food, I raised my ec from the normally golden 1.0-1.1 for this strain to 1.2-1.4. Then today I looked at my blue lab calibration kit and said, fuck it we will check. The reason it got me was that I was whipping a batch of food and measured my usual 5.9 and let it sit for about an hr or 2, when I was ready to water, idouble checked and I was getting a reading of 4.48, wtf. I goto check with the 4.0 solution and I get 4.3. There's my problem.

so I was wondering how often do you guys check your calibration? I checked mine with milk before I had the calibration kit and it was fine so this was a recent occurrence (obviously in the past 3-4 weeks). I kind of figured it was time to replace the electrode in a few more months down the road so I have one on the way.

Whats your standard of time set at?

I calibrate my pen once a week.. The first time it was 0.3 off but now its almost spot on or 0.1

Same here, once a week minimum, but i use mine every day

Do you keep the electrode wet with distilled water? This is a must to keep it calibrated as long as possible and to keep it working well.

I have a Hanna I try to cal once a month it stays fairly consistent.
My first Hanna, same model (98129), got to be every other day, they swapped it out no question.

I use a SUBOTA pH pen and store it in pH7 calibration solution.

I calibrate once a month at least to make sure.

When I calibrate I do 4&7.



J