A note about digital pH glass globe electrode probes

Digital pH probes need to stay wet, they should be rinsed off with distilled water after use. They should not be allowed to dry out and something like this should be used for storage, a drop on the bulb and sponge before the cap is replaced:


I’m wondering why my PH meter does not say any thing about keeping it wet?
I know it says to rinse it off.?

Testing meter companies provide this info in the package. I use Milwaukee meters. They come with calibrating solutions, and I have used them for 10 years. I will get you some links to Meters I have used, and totally believe in.

This solution is highly recommended and much cheaper than replacing a probe.

Another note: Probes go bad. This is another important piece of info you need to know when investing in a testing meter.

Yes, some of these cheaper Chinese meters, they work perfectly fine, and even have really good longevity – if you take good care of them, and maybe re-calibrate them every now and again, but that can be needed even on the more expensive meters.

However, as many may have noticed when ordering any of these relatively decent quality but cheaper knock off electronics from china, the Chinese are not necessarily the best about making a very good instruction pamphlet.

Some may consider these cheaper meters disposable, but in my experience you can keep them working with high accuracy if maintained properly.

There are a few really good meters for not much more money, that will come with better directions, and maybe even better reliability and longevity, and I believe Latewood will be posting some of those links soon.

And the bottle above is huge and will last most people a very very long time, even if used very frequently and very liberally.


Wow!! Yeah i feel like a dumb ass. I did test mine against a liquid drop test and they seemed to b around the same of course digital gives you exact. But I have been drying mine off after each use. Wth.
Huh I’m learning something already. But yes I should have known this. That’s why I signed up for this. No matter how many grows I think there is something to learn always. Hey thanks for the info on the meter storage. Let me ask I use the prong style PH meter in my soil the 3/1 style. Does any body else use these and is there something I need to know about those cuz mine don’t seem to move much and I’ve been trying to get my PH down a bit but hasn’t moved in a week of adjustments. Should I do manual soil tests instead of these meters Thanks y’all.

The long prong metal probes are notoriously inaccurate, unless you get lucky and get good one, and you always have to buff the metal tips and the length as well, polished shiny, right before use, to ensure the metal can make contact with the nutrient salts enough to cause some chemical electric reaction and then make the needle move.


Yeah that’s kinda what I was figuring. Luckily my plants look good but I thought it was strange my gauge hasn’t moved since trying to lower my soil ph. Maybe I’ll try to buff them up like you say and see if that makes a difference but I think I’ll get me a good tester asap. Maybe even get an old school style dropper set just for back up. Hey thanks for the response MacG I will let you know what the outcome was. I’m in week 4 of flower so I’m just trying to fine tune things with a little help from my friends. Peace out and thank you.

Sent from my iPhone

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Question for you Mac or Latewood! Can you use ro water rather than distilled? If not looks like I will be making a trip into town for some distilled.

Yes, R/O is perfectly fine, the point is just nearly pure or completely pure water, in other words 0.0 EC/TDS water.

This water is good for cleaning but not for storage. For storage you need something like in the above link, some pH/ORP electrode storage solution.


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Hey MacG wanted to follow up on the 2 prong soil meters we chatted about a couple days ago. I did pull them out and cleaned the prongs til nice and shiny but what I really noticed was that the switch was corroded and after a couple times rapidly moving the switch back and forth things started coming around. I tested them on the light and water to see if my meter was functioning and it was so I put them back in use and found that my ph did adjust down luckily I check my stuff a lot and it got as low as 5 in ph but only took a day of letting it dry up a bit and I watered with neutral water and is now sitting at 6.5 so I went and invested in a rapid meter to test the soil or water with a simple prong and a digital meter. So I guess my point is as you said don’t put faith in the sitting 2 prong soil meters unless you are going to maintain them weekly and make sure they work right. And I always have to good old fashion way to do it to but that doesn’t get you as close. So I hope this helps and thanks MacG for the insight.