PPM in and PPM out

Hello helpful friends-
I was just wondering if your PPM runoff should always be lower than your PPM input?
I had a lockout situation where my PPM’s out were sky-high. I flushed like crazy and resumed a light feeding schedule. I would hate to go back to my initial troubles. For instance, I just fed my CherryGasm it’s recommended feed with Flora series three part (with CalMag/RO system) and it’s input was 575ppm and the output was 690ppm. I started with a ph of 6.05 and the runoff was 5.8ph. I did a one gallon flush following feeding with RO water at 6.7ph. Is this normal?


Soil when fresh will show a high TDS in the runoff (like 4,000 ppm) but soil buffers the salts differently than running nutes in coco for example. Based on your numbers I’m assuming you are in a soilless medium?

This is too close to really be reliable: you are not actually reading the solids in the liquid with your meter but rather the electrical conductivity and the electronics approximate a value that you then read. Same for PH.

How about a photo?

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I understand these words, I’m not positive I comprehend them. More research on this for me I guess

These are in early flower with Fox Farms soil.
Pistils looking ok, but a lot of the fan leaves a bit discolored. Just confused about seeing slightly higher PPM’s in the runoff than in the input.
For instance, after I posted yesterday, I ran a 4/1/5/3 Flora with CalMag as the 3. The input was 625PPM 6.23pH and the output was 613PPM 6.0pH. Those numbers looked ok to me?

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