Hey Anyone Checking The Ppm After Watering?

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nikson

nikson

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hello farmers ,
are you checking the ppm in water that leaves the pot after watering?

what is the normal and safe range for growth and flowering?

thanks ! :)
 
Enforcer

Enforcer

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hello farmers ,
are you checking the ppm in water that leaves the pot after watering?

what is the normal and safe range for growth and flowering?

thanks ! :)
I don’t unless I’m trying to diagnose an issue. Ideally, I want the runoff ppm to be close to the input ppm. If the level is more than 100ppm over my input, time to flush. I don’t bother pH-ing the runoff. Won’t get an accurate reading that way.
 
H

heisen

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Runoff ppm is impossible to catch.for every extra amount of water that goes into your catch bucket the ppm drops.its soil not hydro.you cant get a fix on it
 
Rootbound

Rootbound

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Runoff ppm is impossible to catch.for every extra amount of water that goes into your catch bucket the ppm drops.its soil not hydro.you cant get a fix on it
Thats why you dump all run off until the last watering slide in a clean catch tray and test it.
 
H

heisen

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Thats why you dump all run off until the last watering slide in a clean catch tray and test it.
Wouldnt all the runoff equate to the total? I can add 10 gallons of ro to 30 gallons and drop the ppm significantly.if your taking away some of the water than it is not your true ppm.
Add 1 gallon to the pot and the first 3 seconds of runoff will be almost twice as high as the last.and that's not even equating the salts that are still locked in the soil.testing ppm runoff is a waste of time imo in soil.
 
Enforcer

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I don’t unless I’m trying to diagnose an issue. Ideally, I want the runoff ppm to be close to the input ppm. If the level is more than 100ppm over my input, time to flush. I don’t bother pH-ing the runoff. Won’t get an accurate reading that way.
BTW, I grow in coco.
 
H

heisen

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BTW, I grow in coco.
That's a whole different ballgame.as long as you know how much your catching from your start ppm and have a solid reference with experience.
I think catching runoff is for experienced growers that can watch there plants and know what the numbers mean.you do it the same way every time.
It may not be the actual ppm number in the pot but you know what the number means to how how your plants look.
 
Enforcer

Enforcer

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Wouldnt all the runoff equate to the total? I can add 10 gallons of ro to 30 gallons and drop the ppm significantly.if your taking away some of the water than it is not your true ppm.
Add 1 gallon to the pot and the first 3 seconds of runoff will be almost twice as high as the last.and that's not even equating the salts that are still locked in the soil.testing ppm runoff is a waste of time imo in soil.
I agree that it’s probably misleading at best in soil. However, it should at least get you in the ballpark. Like if you check it and it’s 3000 ppm, you know you have a problem. And OP, don’t even bother checking ppm with organics.
 
JWM2

JWM2

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I bought a ppm meter recently and freaked out. Flushed my soil and made it even worse. Took a step back and realized my mistake and got back on track.

First time in my life I measured runoff ppm in soil and it just made things so much worse. Lesson learned.

I do check ppm to get an idea of what my feeding solution is but runoff ppm imo is a waste of time in soil. Especially if you are growing organically.

What was even worse is after the flush I had to wait for the soil to dry out to address the real problem. That ended up wasting several days. Oh well. That’s what I get for trying something new, haha.
 
Enforcer

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Maybe I should explain my situation better. As it seems there are some other variables I left out. I grow in coco and feed with synthetic nutes. I have a sump set up to catch all of the runoff from the plants. It pumps out every few days to waste. If I think I’m having a salt buildup. I’ll drop my EC meter in the sump to check the strength of the runoff. As I catch all of my runoff, it should give a reasonably accurate measurement of the total ppm in the runoff. It is usually within 100ppm of my input feed. So if I check and it’s a few hundred or more over my input, it’s flushing time. I don’t usually run into this problem though. I give my girls a weekly AACT flush by hand with Recharge microbes, molasses, and some kelp. I also auto feed multiple times a day. I hardly ever have a salt buildup issue.
 
JWM2

JWM2

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Maybe I should explain my situation better. As it seems there are some other variables I left out. I grow in coco and feed with synthetic nutes. I have a sump set up to catch all of the runoff from the plants. It pumps out every few days to waste. If I think I’m having a salt buildup. I’ll drop my EC meter in the sump to check the strength of the runoff. As I catch all of my runoff, it should give a reasonably accurate measurement of the total ppm in the runoff. It is usually within 100ppm of my input feed. So if I check and it’s a few hundred or more over my input, it’s flushing time. I don’t usually run into this problem though. I give my girls a weekly AACT flush by hand with Recharge microbes, molasses, and some kelp. I also auto feed multiple times a day. I hardly ever have a salt buildup issue.

For sure. I wasn’t referring to you I was just relaying a recent experience.
 
Enforcer

Enforcer

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For sure. I wasn’t referring to you I was just relaying a recent experience.
No worries man. It wasn’t in reference to your post. I just realized after @heisenbubble post I should elaborate on the variables in my situation so people know where I’m coming from. Some many different ways to grow. I should probably put all that stuff in my sig so I don’t have to type it all the time lol.
 
nikson

nikson

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I'll explain what happened I grow in coco and perlite 60/40 , There are 3 plants about 15 liters of pot. began to show signs of distress. I washed one of them in 5 liters of tap water. (I have nowhere to get ro water.) I took a runoff sample toward the end. The ppm was about 6000 I do not know how it happened and what made a mistake because I work with a table and never check the runoff. I saw the number that was a bit scary so I washed in 15 liters of water and now it's about 800 + - ppm. When tap water here come with 200-250 ppm.
so i did it to all the others.
and i decided that i would always check the runoff water and go according to the rule not to exceed 1000ppm for a big plant. 500ppm for the young plant. What do you think ?
 
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Enforcer

Enforcer

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I'll explain what happened I grow in coco and perlite 60/40 , There are 3 plants about 15 liters of pot. began to show signs of distress. I washed one of them in 5 liters of tap water. (I have nowhere to get ro water.) I took a runoff sample toward the end. The ppm was about 6000 I do not know how it happened and what made a mistake because I work with a table and never check the runoff. I saw the number that was a bit scary so I washed in 15 liters of water and now it's about 800 + - ppm. When tap water here come with 200-250 ppm. I decided that I would always check the runoff water and go according to the rule not to exceed 1000ppm for a big plant. 500ppm for the young plant. What do you think ?
The flush was a good call. To avoid salt buildup in the coco again, water daily until runoff. The ppm of your daily waterings will vary a little due to your genetics. But 500 ppm per feeding is a good starting point for a medium size plant. Letting the coco dry out between waterings is what causes the salt buildup. That is the soil method for watering. Coco needs to be moist all the time.
 

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