So I got a ppm reader digital I run about a gallon of water through the plant and test run off at then end it’s about 345 I make my solution up of fox farm trio nutrients and it reads 1300 I water the plant and test run off at the end and the number reads 745 is this good like another example 500 ro 1200 nutrients 760 run off …I’m willing to listen to get this understood
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I should be more specific and say medium is soil and water ppm is 244
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This will be a good thread I’ve only lately myself started worrying about my ppm my tap water ppm is 34 I was told to bring it up to 200ppm as a base before I add nutes,
I’m going to sit back and read this thread,I’m wondering do you have to calibrate the ppm meter I have a cheap one
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@anon98660487 they have calibration powders you can order for a definite calibration …I’m past that part I’ve used the ppm reader twice think I’m doing it right but idk we will let the knowledgeable ones answer lol
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Someone wiser than myself should take this Bc I’ve only ever tracked TDS with hydro. Personally, I don’t see the benefit in measuring the TDS of your runoff in soil. PH seems to make more sense, but soil will also act as a buffer (unless you’re using something like peat) so depending on what nutes and soil you’re using, this may not be incredibly relevant. If you’re using Promix or something else inert, both TDS and PH seem to be more important, but I’ve only ever grown DWC or soil so can’t speak to Promix or Coco.
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Soil here bud only reasoning got one is because I’ve been trying to correct this problem I am having with the ladies
Ppm after clean water is always around 3-400 so I take she’s hungry but she displays nute burn with the tips ?
Up your calmag. The plants need the extra iron to use the nitrogen without burning as much.
So your ppm is dropping from when you water to run off. It’s leaving those residual salts behind in the media, that’s why you see it drop.
@anon98660487 I haven’t heard that before, what are they saying you should use to get there? I’m guessing they are thinking of that 200 ppm as a pH buffer, pure RO water takes the tiniest bit of pH up or down to change the pH drastically, my hardest to pH water is for my soil, it only gets calmag and pH down, I almost always over do it and have to add pH up.
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So I need calm again to correct issue with my plants ?
I use 1 tsp per gallon always, every water. Then add food if needed and adjust pH.
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I will see the result of the feeding the next couple days and respond from there …tip burnt yellow spreading from top of plant down
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He uses calmag and Epsom salts to get it up to 200ppm,I’m on the fence about it,but he does grow pretty good weed,
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I was confused at first too, but this makes sense with your explanation @anon98660487. Adding micro nutes (calcium, magnesium, sulfur, etc.) to bring up your TDS before then supplementing with macro nutes (N/P/K). I’m thinking your buddy’s logic was saying that because your tap water’s PPM is so low, it’s void of micros so those need to be accounted for before adding your macro nutes. His target of low 200’s was likely giving you a baseline TDS of sorts to then add your macros, and to then reach the end goal of not burning your plants by arriving at a desired PPM.
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I do just the contrary, first the basic nutrients line, but a bit less than recommended. Then, upon what the plant needs at that stage, I add CalMag, Epsom salts, molasses or other complements but alternating them in consecutive feeds until I reach the desired ppm’s … 
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Does molasses bring the ppm up,my early grows I used powdered kelp and molasses,that’s it I didn’t even own a tds or ph meter lol and my plants were pretty lush,
Then I go buy meters nutes and shit ,I’ve had a few shitty grows lol not super shitty,but shitty enough of you know what I mean
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I did the same damn thing! Growing nice plants, discover pH and ppm, get meters, start screwing shit up. I threw them both in the trash awhile ago and my plants are nice again, go figure.
My tap is ~80ppm, if that meter was ever to be trusted. I didn’t add anything to it at all for first ~4 weeks in soil. Aways did me right. Now in coco I’m obviously adding food and cal mag
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My tap ppm is 40 very soft , I add canna calmag , Epsom and iron till Rez says 250 then I add my npk etc
@anon93244739 if you always overdo the ph down , try watering it down first in Separite bottle and use that mix instead , say 1/4 , ph down to water , I never use pure ph down , way too troublesome
A good tip , use canna rhizo tonic in veg as a ph up , amazing results in vigor and vibrancy in 4-5 days after use : )
Using ph down bring ph of Rez down to 0.3/0.4 lower than you need , then bring up with rhizo to desired ph , this is way less than recommend on back of bottle but very effective so expensive bottle lasts a lonnnnng time , so actually cheap to use : )
I found canna rhizo to be better than hg root excelorator
Hg excelorator seams better value as they say more concentrated but they add a lot of other stuff in bottle to legally change from canna ( copyrights etc ) so the concentration of what really counts is actually less in bottle kind off than what’s in canna rhizo : ) don’t be fooled by fancy shiney metal bottle : )
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Yes they do, I use them is the first weeks of flower stage, here you can find more info about them:
More about molasses info from The Three Little Birds. It really is great stuff. 
3LB - Molasses Manual.pdf (39.3 KB)
