Sunmallow PH tester problem?

I can calibrate no problem with the 7 solution. But when i put it to calibrate in the 4 solution it doesn’t calibrate to 4 Ph. Stops around 3.76 ph. Granted the 7 solution only calibrates to 6.86 and not 7 exactly like it should. Thought it might be me but i have tried it over 20 times and the same outcome each time. Should i be concerned with the 3.86 and not worry about it seeing how it is calibrated at 7 ph with no problems? And i get a error message each time when i try the 4 solution.

If it’s new, I’d contact the seller and see if they’ll replace it. If not, you know your meter reads .2 lower than actual so you can correct your ph .2 higher to get where you want to be.

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Yup was considering that until i pick up another one. Can’t return after Jan 31. Was only $15. I went ahead and dropped the seads in the ph’d distilled water. Didn’t have to make any adjustment on the water.

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I am assuming you followed directions for calibration? Is it a pen that needs to be calibrated with 4.01 and 6.86? Or is it a different type?

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Your calibration is no better than your solution. It is easy to contaminate solution when doing a multi-point calibration. Good practice to wrench probe between buffers and dry with cotton ball. I like to keep new solution available. Good luck

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Yes it needs to be calibrated with 4.00 and 6.86 solution. Yup followed the directions.

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I didn’t use the packets it came with. I had bought the General Dynamics 4.00 and 7.00 solution instead and used that. Followed the directions and put it in distilled water each time after using the buffer solution before going to the next solution. I did wipe the probe with tp thoough.
Ordered the
Not sure what you mean by wrenching the probe?
I did order the Blu Lab PH Pen last night and it will be here tomorrow. Pricey but what i read well worth the money.

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Sorry I meant wash with distilled water between buffer solution which you’re already doing. Getting your new pH probe and new solution I feel like you’ll be right back on track. good luck

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this is the biggest problem, a cheap meter.

u should have better luck with the Blue Lab stuff.!!
WIN_20181001_17_33_52_Pro

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If you use distilled water and don’t add anything (other than say peroxide) you do not need to PH the water. There is nothing there to actually be reactive.

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So @Myfriendis410 i take it this is just for seedlings and once i get it to poke it’s little head into it’s new environment that is when i need to worry about PH? Thanks

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If you water with NO additives and use straight distilled or R/O water, the liquid will adopt whatever the native PH of the media. Instantly. There are no hydrogen ions in the water to “hold” a PH. If you took a reading it would be all over the place because there’s nothing to read.

So you can water any time you want with PURE distilled or R/O without PH’ing. The moment you add nutes you add hydrogen ions (PH stands for Potential Hydrogen). THEN you PH you liquid.

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Thanks again @Myfriendis410 i would have been checking the PH and driving myself crazy for the two weeks i am waiting to add nutrients.

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