Help me understand PPMs in soil. What goes in VS. What comes out

  • Thread starter SeeAirAhh
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SeeAirAhh

SeeAirAhh

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First time growing in soil, I understand PH and how to balance that by looking at my runoff. I also do PH tests of the soil, but im struggling with understanding my ppms. So i had realized my ppm meter was throwing me off a while back. it read 125x10, but the x10 was so little i didnt see it, well that was handled and i was sure to feed it plain ph balanced water to lower that back down to about 800 ppm runoff. So going off of my PPM runoff, when should i give it nutes? I feel like i made a mistake, i got the ppms down to 800 after giving it plain water for a while, and then i gave it a feeding of 400ppm, and the runoff shot back up to 1100. should i be waiting for the runoff ppm to get down to 200 before giving it nutes? these plants are only a couple weeks into veg so ppms should be around 600 i figure. Should I keep the runoff at 600 ppms then, and just try to balance it out that way?
I appreciate any help in understanding PPMs and what the runoff means!
 
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AKgrow

AKgrow

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Do not worry about doing run off tests in soil, it doesn't help. You can take pH tests in a slurry if there are symptoms of problems, but soils should regulate their own pH. As far as PPM, take reading of your nutrients solution going in to make sure you don't overfeed, or use organic supplements that take time to break down. Good soil is buffered to regulate pH and taking runoff ppm readings in soil will drive you crazy. Just start with good soil and measure what you put in. I personally just use dry amendments and water with a hose. I don't ever worry about pH or ppm unless something comes up.
 
lvstealth

lvstealth

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when you say soil, what do you mean?

let me know a brand, or mix you use and maybe i can help.

many soils have buffers, and what you do to it when you go for runoff to test is not so good for soil that has good stuff in it. but there are other things i hear people call soil, like some of the coco mixes or the soilless stuff.

ph in soil is not the same as ph of water. you dont do a lot to the soil by using ph'd water to try and change it.

if the soil is a store bought mix it most likely has a buffer. so you add stuff to your water to get it to some number you like, add that to a soil that insists that anything that enters be altered to its ph.

you can make your water 7.5 and your soil takes it to 6.0 every time, but the problem is that stuff you added accumulates in that good soil and fights with the stuff the soil has in it. so now, in trying to fix your soil with your water, you have created issues you will have a hard time curing.
 
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