Can anyone help understand whats the purpose of checking t.d.s… so i check tds of some of my plants today while watering. These are in the 2nd week of veg and reading are around 1500? What is one to do with this information. Should i not feed them nutrients again untill i get under 900 . I read that you should be around 800 to 950 til late veg and get up to 1000 in late flower. I would like to think that im not just reading numbers for nothing. Can anyone help me out on this. Im in 5 gallon fabric bags, soil media ( jungle growth soil if it matters). Thanks in advance
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I would not worry about feeding or monitoring runoff for 6 weeks, assuming quality soil. Later in veg when the plants’ root system is fully established is the time to determine salt levels in your medium. And a good metric is runoff TDS under 1,000 ppm or 2.0 EC you would start to supplement.
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With that said would 1000 ppm be a good place for lower as well or is it really how the plant reacts.
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So tds (total devolved solids or ppm (parts per million) are both used to give us an idea of what nutrients are available in the growing medium.
It can be very useful information to keep a healthy plant or help determine how to make an unhealthy plant healthy.
It’s can get very complex but what you’ve read is pretty accurate but not set in stone like many other things with growing plants, each plant and situation can be very different…
Like you say you’re plants tds is 1500ppm for example.
That is what we would call a high ppm, but it’s not necessarily a bad thing.
Are you’re plants healthy and growing good?
If no.
Then the medium may need flushed with plain water till the ppm gets down to 800-1000.
If the plant is healthy and growing good then no reason to flush it to drop ppm, but rather do as you said, just give water the next few times and once ppm drops to 600 or so, feed 500ppm or so to land it back around 1000ppm.
The idea is that most mature plants will grow good around the 600-1200ppm mark so thats always a safe bet.
But some can function or even love higher or lower ppms.
Light intensity and environment can impact nutrient uptake aswell so there’s lots of things at play.
It’s impossible to learn everything it a short period so just keep reading and talking to folks, basically exactly what you’re doing will get you where you want to be.
Just have patience and remember growing cannabis is a process that has no “1 right way” and you will find yours 
I grow mostly in coco-coir just because it’s simple.
Coco-coir is fed everyday and no need to ever check runoff numbers unless something is wrong with the plant.
But I do grow some in soil also and I only really feed in flower and I try to bounce my runoff ppm from 600ppm to 1000ppm give or take a couple of hundred. The numbers don’t have to be exact but hopefully that gives ya a little better understanding 
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Thank you great information. Will definitely keep thin in mind as i go grow.
So now that im awake yesterday’s reading at 1600 flowering across the board. 2 on 2nd week and 1 in 5th week and 1 at 8 weeks. I reckon i need to be adjusting and feed ding per plant not as a whole if that makes sense. I usually just mix up nutes and feed . I use 3 gallon per cycle but i also bottom feed as well. I probably should feed nutes the following with a water to adjust ppm per plant . I think i been doing this all wrong still 
. Like i said i mix up 3 gallons and feed plants till sprayer is empty. So on average the ppm of a feeding day is in the 2000 ppm range. For the most part to my knowledge they look ok. But i do notice one has praying fans,thought it was light intensity but only one is doing that. Funny thing is out of all that one has a higher ppm reading then the rest.i think im gonna skip a feeding and get these ladies off the juice for a bit and see what they do.
