Just delivered qb 260xw!

I’ve been using the 1 on right. Calibrated them both with the same solutions

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Light flip 12/12 last sunday




Watered today, will trim some leaves tomorrow

Trimmed some leaves. Added lime to top of soil and worked in as best I could trying to bring soil ph up

My water drops pH like that when I add Grow big, not so much on Big Bloom. I was starting at 6.5 pH and after adding the FF I was at 4.1 to 4.3 pH. I used ph up to get it back to 6.5 pH.

Nice looking plants :grin:

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Adding lime dry can lead to pH problems in the soil. You are better off adding a pH’d nutrient solution instead.

I already have ph problems. I usually add lime to my soil but didn’t this time for reasons I won’t get into. Didnt add much. See numbers above

Did you calibrate the pH meter prior to use and check to make sure it still is calibrated at every use? You are right, 4.7 doesn’t seem right.

2 meters above calibrated with same 4 & 7 solutions. Even temps dont match

Are you rinsing the tips with water and shaking the moisture off just before you dip it in your test solution?

Distilled water

I’ll watch and water in a few days and check numbers again

Distilled water will be a bit wonky with pH since there is no buffer in it, so any calibration fluid on the tip will throw it off. If there is >200PPM in the solution I would trust the pH more although that would be if nutes were added to it. NaCl could raise the PPM but not the buffering capacity and still be a wonky as water.

Ultimately you want your input pH and PPM to equally your runoff PH/PPM. But if your meters don’t work you may be throwing darts. I have a hard time believing your pH meters are both broken, so there may be a method/procedure thing going on.

Of course🤦‍♀️

I’m a little confused, are you trying to PH distilled water? if so, that’s your problem. distilled water won’t give an accurate PH reading because the ppm of distilled water is too low.

Tap water. Give the meter a quick rinse with distilled and dry before using

Bought a ppm meter. After calibrating old and new…big difference. Never said they were both broken. Calibrated both with same solutions. Don’t know which to go with

This is a goal I’m not meeting

Can you also describe how you calibrate the pH meters? It should be a two point calibration. First @7 and the second point @4. You cannot calibrate with only a single solution since you need to establish the correct slope. This may be why the two meters show different values. I can’t see the brand and model numbers, but they should have come with instructions how to do a two point calibration.

Both solutions, both meters