Help! pH is 5.5 and 5.6

I fed a grow booster mix of 6.6 two days ago and runoff was 5.5 and 5.6 for these two plants. Used distilled water.
For my next water/feed I’ll use RO water and stick with that but how do I get my pH back to mid 6’s?
(5 days into flower)

Do you have any pH Up?

I do. Never used it (my first grow).
How do I go about using it? The more I looked online about how to use it, the more confused I got.

My thinking was if I put more grow booster (from ILGM) in my gallon water/mix it would get my pH closer to where I need to be. BUT I wasn’t sure…

You use the pH Up in small increments in water until you’ve got your ph where it needs to be. What is Your pH now? Are you growing in soil?

Do I mix it by itself in RO water, or mix it with grow booster in water? What should my pH be in the mix before feeding?

If your runoff pH is higher than your starting (water) pH, use this equation to determine your soil pH:*
Soil pH = Runoff pH + Difference

If your runoff pH is lower than your starting pH, us this equation:
Soil pH = Runoff pH - Difference.

For example, say your the starting pH of your solution before it goes in is 6.5 and the pH of your runoff is 7.0. The difference is +0.5, so using the above equation:
Soil pH = 7.0 + 0.5*
Soil pH = 7.5

If your starting pH is 6.5 and your runoff is 6.0, your difference is -0.5 and using the above equation:
Soil pH = 6.0 - 0.5
Soil pH = 5.5

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Yes, growing in fox farm ocean forest soil. pH was 5.5 in plant on right, and 5.6 in the other.

I’d pH the water to 6.5 then add maybe .03 ml of pH Up then retest the water.

Ok, I think I understand the the equations. So my starting pH was 6.6 and my runoff was 5.5 then the difference is -1.1
Is that how much pH up I add?

Thank you! That’s what I’ll do. I appreciate your help.
(I’ll pH water to 6.5 then add .03ml of pH up)

One more question:
Should I be feeding nutes every time I water? Have been so far since the middle of veg

Personally, I listen to my plants. They will let you when they need something. Is there any particular reason you are feeding every time you water?

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At this point I’ve been feeding just to get my pH up. Mayb I should just use pH up this time? Get my pH to the high 6’s

That’s what I’d do because more than likely the nutrients are in the soil just not able to uptake them due to low pH.

Hope others don’t get offended but you can put a couple gallons of straight water through without the chemicals. After filter my water is 7.6. I had this issue cause promix adds stuff to buffer ph so I flushed with straight water and I was back on track. Then I started adjusting mix before I watered the next time.


When growing in pots, until you get the hang of it you’ll have to do the ph dance.

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Now my ph stays perfect and all I do is use one gallon of normal nute mix as the bottle suggests, then add three gallons of water to that and bickady bam I’m at 6.0. No ph buffer at all. With all the micorrhizae (beneficial fungi additives ) and liquid karma she only want 1/4 of the recommended nutrients.

. Here is one of my ladies, ain’t she a looker?


She sure is quite the looker. Thanks for the. Tips. :blush:


Very nice indeed! Did you top or FIM?

…so I experimented with the pH up on two other plants. It was an interesting outcome:

Both plants were 5.5 pH last feeding
I added pH to one gallon of RO water til I got pH reading of 7.1
Runoff was 5.6 and 5.7 in the other. Nowhere close to where I thought they’d be.
So, I think I’ll add more pH to RO for the two plants above. Maybe high 7’s low 8’s
And yes, this pH is a tricky thing right now.

What do you mean by “straight” water? RO water be okay?