How to properly measure soil slurry

Ok… I have realized that there has to be a formula for testing ppm … example:: If I were to take 8oz. of soil and 8oz of water and mixed it and filtered it, I would get a certain ppm result… now, if I were to change that to 8oz of soil and 16oz of water… the results will be different…so my question is… what is the PROPER FORMULA for testing ppm???


I would recommend 1:1 ratio when doing this.


I read a conversation on here last night that you mix ⅓ soil with ⅔ pH 7 water solution, mix well and let sit for 10min. Filter and test… I’ve been using one of those k-cup coffee screen filters… to filter my slurry… I did this formula and I got 800ppm when I tested a FF ocean and Roots Organic 5:1 soil ratio prior to my 5gal transplant
… Super Silver Haze feminized 45days old from sprout…

It’s 15 inches tall

I have always been told / read to use distilled water. That way the soil’s pH is not being affected the pH of the liquid. Since Hanna is a trusted name in measuring equipment, I rely on what it says.



Same here with distilled water at 1:1 and rest it for 12 hours minimum.

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How does my plant look?? And how about the age compared to it’s size??? Should it be bigger

Make sure you get your slurry sample from 2 inches bellow the top of the soil. I use a sterilized metal tube to collect a core sample from the soil about center line between the stem of your plant and the side of the pot. Then mix 1tbs water and 1tbs soil. Mix for one min, really work the soil and water around. Next wait 15 mins to allow the liquid to absorb and mix with the soil, as well as soil settle to the bottom of your vessel. After 15 mins get ph and ppm reading. Be sure to use pure water like RO or distilled. Water Must have less then 200 ppm in order to get accurate readings.

What about well water… mine is 6.2ph and between 150-200 ppm… shouldn’t I filter the slurry before I test the ppm

My bad… I just watched the video… I totally understand the process… FINALLY… and. THANKS FOR THE VIDEO

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I put more emphasis on health and structure than physical size. These purple haze are 43 days old. I think they are between 7 to 11". One is naturally a little smaller than the other three.

And, they have all been topped twice and trained in the manifold form. One on day 36

Your plant looks healthy. Size - no idea


I took the soil sample.
… going down in the soil, I easily dug up some tiny/thin roots… won’t this damage the plant

It’ll be okay, there’s plenty more in there.