pH adjustment question

What is the best procedure to adjust pH? I have started checking pH after nutes are put in the water. I use the Fox Farms trio and CalMag.

The reason I ask is that I tried to adjust my pH up after the nutes were in and the pH didn’t move hardly at all after 3-4 CC’s of pH Up added to a gallon of water/nutes.

What’s the best way?

adding 3 or 4 ccs Up per gallon should theoretically raise the pH at least 0.6

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Hmm, I got about .15 up at best.

Sometimes chemicals can also serve as buffers to absorb the impact of changes in acidity.

Also, is it possible your pH meter is out of calibration or off scale?

Let’s think about this What is the pH your source water? What brand and concentration of nutrients are you feeding?

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I just got a new Apera PH 60 meter, just calibrated it and checked it against the calibration solutions after trying to raise the pH.

I use Fox Farm trio and an organic CalMag.

I mixed about 40 cc Big Bloom, 15 cc each of Tiger Bloom and Grow Big.

I use a chlorine filter on my tap and pH from tap is 7.63. After adding nutes, it read about 6.0.

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And! I also put in 10cc CalMag.

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I don’t see why this is happening. Perhaps someone else more experienced than me can help.

Would like to continue to follow the discussion

I’m wondering if the organic CalMag isn’t acting as a buffer.

Next time I try pH the feed mix, I’ll do it BEFORE the CalMag.

You could also try feed water(cal/mag) feed water(cal/mag) I dont use it but I want to say I seen others do that here. :man_shrugging: Giving cal/mag on only water days. Noob and I grow organic so just winging it here :joy:

Ah, you’re saying nutes only in the water and then on water days, THEN add the CalMag to the water, correct? So it alternates, CalMag/water and nutes/water?

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Yes that’s what I’m saying. But idk if that will fix your problem. Definitely want someone with more knowledge then me. Idk anyone to tag though :grimacing: . Let me do some searching and see if I can tag someone

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@Fieldofdreams @dbrn32 idk if you guys are soil guys? But I bet you know who are if not! Can we get this guy some help?

Thanks

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Hey there. I’m late here but let me try and get a handle on your situation. So to start after running your tap water through a filter before nutes your ph is 7.63. Then after all of your nutes have been added

it drops down to 6.0. From there you want to raise it in the range of 6.5-6.8? My first gut instinct is that your filter is turning your tap water into distilled or r/o which is a neutral and can’t ph properly. What is the filter your using? If you strip all of the tds out of water the ph pens have a very difficult time measuring.

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@RobS1973 try this; set out an uncovered container of tap water for 24-48 hrs and it’ll dechlorinate itself and then get a ph reading on it. No filter. Then add your mutes and ph again. Adjust accordingly and see what happens.

I believe I was still testing tds at around 300 after running thru the filter. I’ll have to verify that though.

I’ll also set out a few containers of water and just let them sit for a couple days to see what happens.

@RobS1973 hmmmm. That’s high enough I think for a reading. And the pen tested good in the 7.0 solution and the 4.01?

@RobS1973 I use an r/o filter and it gets mine down much lower so that might not be your issue. What ph up/down solutions did you buy?

This is the filter…

The pH chemicals are by General Hydroponics.

Yep, pen was accurate when I tested it in the calibration fluids. I had just calibrated it before using it the first time so the calibration liquids were right there.

Weird huh? The only thing I can think is that CalMag is acting as a buffer.

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@RobS1973 I’m unfamiliar with it.

Set some straight tap out tonight and let’s run some tests on it tomorrow night and inbetween we can tag a few much more experienced growers in here.

Maybe with a few more brains on this we can wrap our heads around the issue collectively. I’m kinda stumped at the moment.