Water pH testing and runoff?

Hey gang; just soaked and planted - sprouts ~10mm tall now after 36hr.
I’ll be the 1st to say it - I’m a newbie and I don’t know what the hell I’m doing! With that said; I’m trying to read and understand other posts on this an similar topics. Here we go…
My tap H2O is filtered ‘Zero Water’ and tests at 9.8pH. I used this to soak and also water/moisten the Germination soil in which the seedlings have begun to grow. I have 4 other seeds soaking and have popped - almost ready to plant.

  1. Should I adjust my pH in H2O prior to use in germination soil? If so, then how to lower the pH?
    I have Vivosun pH and TDS testers.
  2. What is “run off” and how do I get an accurate pH of the soil?
    Kindly RSVP ASAP.
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pH is best adjusted all through the grow, even sprouting.
It will tolerate the wrong pH early as the roots are not absorbing anything yet. But you are going to have to get that under control. Seems high even for city water. Do you know your PPMs ?
If its like RO or distilled any reading is suspect as distilled water is neutral and very hard to get an accurate pH reading. You wont water to runoff til the plant gets larger, like 3 weeks or so.


We can provide better help with some more info.
COPY/PASTE the below list into your forum post.

Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so; Or post
NA (non applicable)

What strain, Seed bank, or bag seed

Method: Soil w/salt, Organic soil, Hydroponics, Aquaponics, KNF

Vessels: Pots, Grow beds, Buckets, Troths

PH of Water, Solution, runoff (if Applicable)

PPM/TDS or EC of nutrient solution if applicable

Indoor or Outdoor

Light system

Temps; Day, Night

Humidity; Day, Night

Ventilation system; Yes, No, Size

AC, Humidifier, De-humidifier,

Co2; Yes, No

Vivosun meter PPM is 0005. The H2O (City tap water) is filtered using a ‘Zero Water’ filter - popular in USA. The TDS meter that comes with Zero Water filter shows 1.
With this in mind- how do I lower the H2O pH? I have pH-Up and pH-Down in bottles.
Once I have a more pH balanced H2O - do I need to flush the Germination soil (in Jiffy pots)?
I have the same in spray-bottle that I’m using 2x daily on sproutlings.

If the ppms are 0 to 10 you don’t need to adjust it at all.
Its already neutral. As I said in the other post many meters cant read very low ppm water to give you a pH. If that’s what you have been using you dont need to flush.


And water filtered to below 10 ppms or so is exactly the same.


Thanks, but even more confused…
How can pH and TDS correlate?
My city tap water measures 8.8pH and ~150TDS.
The filtered (Zero Water) city tap water measures pH9.8 and <5TDS.
I see others in ILGM posts say that (pp) “…my non-nute water is ~6.5pH…” so there must be a reason why to use pH adjusted H2O, and a manner to adjust it for simple non-nutrient watering.

because like the article i posted says, meters cant measure the pH of water with virtually no ppms.
Your water of 5 ppm is no doubt a ph of 7. But your meter cant detect it. Its not the way they work.
It may measure 9.8 but its not. My meter just bounces all over trying to read Reverse Osmosis water of 10ppm.

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Okay that I understand - extremely low ions cause pH sensor/meter to provide false readings.
However; the city UNfiltered tap H2O measures at 8.8pH.
Are you saying that by filtering the city tap H2O, now with ~5TDS, then the pH should lower to ~7ish?

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Yes, exactly, but your meter wont be able to measure it. Just trust that its ok.

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What are you growing in.
Soil? What brand and variety?

Whew…okay…emergency rise aborted!
Thanks Spiney_N.

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Oh right…
Growing in… from my earlier post: Germination method and soil - NEWBIE Please advise - #2 by Covertgrower
Germination soil in 3" Jiffy Pots. which will go directly into FF Happy Frog 3/4 with 1/4 FF Cultivation Nation Coco-Perlite mix.These were potted Sunday PM.



So #1 those are too wet. Dont water anymore for a couple days until it dries out some.
2, those little drops of water will burn the leaves under the lights. Like a magnifying glass they focus the light on those baby leaves. Take a klenex and dob the droplets with a corner and get them dry.


Oh sheeeeit!
Okay - done.

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Those peat pots take too long to decompose and will bind up your roots. So when you get ready to transplant you should slice the sides and remove them. Or at the very least put enough cuts in it so the roots can escape.
Here is a photo of a plant where they left the peat pot. If you look close you can see a circle on the surface of the dirt.

Ahh…and I suppose they’ll definitely take to long to decompose for Auto-flowers. Okay - I’ll cut-em-loose in a couple of weeks.
Too wet…should I un-cover them while lights are on? Was trying to keep both soil moist AND temp up closer to 80F.

Covers are kinda personal preference. I keep them domed for 2 days and then remove it at lights out the second day. By morning they are dry and they will be fine. Others keep the covers longer.
This is in plain Happy frog at 3 weeks. Nothing but plain filtered water.


Well…they’ve been covered since I put seed in soil. They’re moist, as you can see, droplets and all, which I removed. I’ll leave the covers off for a couple of hours and put’em back on for the remainder of lights-on - until 08:00AM tomorrow.

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