Ro/Distilled water

Good Morning I was reading on here last night and saw a comment that mentioned if you’re using RO or Distilled water you don’t have to ph the water since it will ph to whatever your soil ph is. Is this correct? I use Distilled water and always put it to the correct ph before I use it so I’m trying to get more info on this but can’t find the topic or comment. Can someone please explain this thank you. I hope whoever commented this I didn’t quote you wrong or misunderstood you

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You are correct.
You cannot even test the pH of distilled/RO water as it is neutral. You can try but your meter will simply read random numbers. Do not try to adjust the pH either.
Just use it as is.

https://camblab.info/testing-the-ph-of-distilled-water/

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@Spiney_norman ok thanks makes sense since when I use my ph meter the ph goes high so I lower it to 6.5 I’m going to try and just use it like that straight out of the jug thanks again

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I use RO water exclusivly and never adjust it when using it plain.
Now when I begin feeding then it becomes necessary.
Once the PPMs go over 100 you can accurately read pH with your meter.

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@Spiney_norman i top feed and I’m using roots organic how would you test ph for top dressing? From run off?

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Yes, run off is a good place to start.
If you encounter problems then maybe a slurry test.

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You can’t really pH RO/distilled water without adding something to be pH’ed. When feeding, since it is neutral, you can add calmag or silica (if using silica, it needs to be mixed vigorously and allowed to set for 20 minutes or so before doing anything else) and they will give you your baseline. You would then add your nutes and adjust pH from there. When using RO/distilled alone, for waterings only, just let them have no need to adjust. Only worry about adjusting RO/distilled pH when using it for feedings. Waterings your fine.

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@Spiney_norman can you please explain what a slurry test is I’m new to this and this is my first grow so I’m trying to learn everything I can thanks again

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Great post and responses! I’m using r/o and hadn’t heard/read that. Phenomenal forum, every day I continue to learn new sh!t lol. Fantastic

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Basically for a slurry test use a 1 to 1 mix of the plain water you mix your nutriens in (but just plain with no additions), and some soil from a couple inches down in the grow bag.
1 to 1 would be for example 1/4 cup water and 1/4 cup soil.
Mixt together and let set for 15 minutes.
Test pH and PPMs. See where you are.

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This video shows him doing it by weight, but the way it should be done is by volume.
This weights and measures system we have using the term ounces for weight and volume both is confusing. What you do is use the same “Volume” of each. So 1/4 cup (which is 2 ounces) of each water and soil. The best advice I have heard also is to use the same water you use for your plant. If you water with distilled then do a slurry with distilled. If you use tap water then do the slurry with that because that’s what you have in the soil all the time.
And since you want to know the current pH of the soil dont adjust the pH of the water for the slurry. That will just throw off the results.

Agreed. But he does measure the water by volume, although he does weigh it.

And when I do a slurry test, I use distilled water, which never needs to be adjusted. That way you can determine the pH of the soil.

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He gets the right result. I actually think this is a better video about a slurry test than I have ever found. Its great.
If he had just measured the soil as 2 ounces by volume it would have been easier to test. I think he got too much soil to water. But its no big deal.
Thinking about it I wonder if the exact measurements are not that important. Take some soil and add enough water to get a reading. With distilled like you say I can see the PPMs fairly accurately too.

I think as long as the volumes are roughly equal, that’s the important part.

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@Newt @Spiney_norman i have a question for both of you if you have time to answer. So i just joined the group a few days ago because my plant leaves are curling and wrinkled. I posted pictures and I had comments saying it was the claw and nitrogen toxicity and I should feed my plants the next few time with just plain water no nutrients. Since I top feed. I fed them plain water yesterday morning before I went to work came home and I see again more leaves with the claw and wrinkling of the leave does this take time to correct or am I doing something wrong to correct my issue. I’m in week two of flower and don’t want to hurt my plants and want to correct my issue before I hurt my girls. And I don’t know if this issue will hurt my yield if not corrected right away

Is this what you mean by clawing?
The twisting in the new leaves?


@Spiney_norman these are the two plants doing it they mentioned nitrogen toxicity do to the claw and dark colored leaves

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Ok. I would agree with excess nitrogen, and you may have been told to just use plain water for a while. That is the right advice.
Now those leaves will not recover so you watch new growth. How is that looking?
And BTW, this is why we suggest sticking with a single thread/topic that you create so we have a good history. It helps up all.

@Spiney_norman i understand the single thread for this just wanted to see what you thought since you was on here giving me valuable information so I’m sorry for asking a second time On a different post. I haven’t seen new growth but I’ll check again tonight when I get home from work. Thanks again

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