Proper way to measure ppm?

Indoor Growing Climate
21

I know it’s explained above but my dyslexic brain still needs to be walked through.

It’s a fem Gold Lead in the 2nd week of flowering in a 5 gallon smart pot. I use tap water that’s been sitting out at least 24 hours. Here’s what I did:

I typically give 2-3 gal per feed.

Fed Jug #1 : pH’d water 6.0 = 191ppm (I was told to do this to flush out the salts that may be sitting in the root zone)
Fed Jug #2: pH 6.1 + nutes (1 tsp/gal Bergman’sflower wk 2 schedule) =1240ppm

Run off: pH 6.3 1200ppm

So would the ppm be (191+1240)-1200= 231 ppm!

Feeding schedules
Feeding schedules799×1251 134 KB

Bergman’s soil schedule asks for 850 ppm. Is that going in our coming out?

I was worried I was underfeeding, so I made another gallon jug ~2 hours later: pH 5.9, 2190ppm (1.5 tsp/gal).

Runoff: 1910 ppm pH 6.4

2190-1910= 280ppm WTF?? So does this mean I need to up the nute mix until runoff is ~850 ppm? Or is this telling me that my plant is eating pretty much mostly what I’ve fed thus explaining the low ppm?

@Countryboyjvd1971 @MattyBear @Sixpackdad

22

@Hellraiser would know!

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23

That would be going in.

Not sure why you’re doing this math, no real point to it.

No, they want the water/nute mix to be about 850ppm going in but if you are using tap water then it’ll be more than that using their dosage directions as tap water adds ppm as well.

No, the water/nute mix going in should be around 850ppm. Your runoff is not 280ppm, your runoff is whatever your TDS meter tells you it is - 1910ppm, no math needed.

You don’t have low ppm of runoff, 1910ppm is quite high - due to the 2190ppm nute mix you gave it.

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24

@Hellraiser thank you!

<>unnecessary n00b chronicles

The only reason I’m focusing on ppm and pH is that all of my plants suffered from nute lock for weeks because of a faulty pH monitor I was using (replaced with the pH20 thank god). Now I’m obsessed with making sure they stay healthy :confused: .

</>unnecessary n00b chronicles

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