EC and PPM

I am having a heck of a time with EC. I am using foxfarm nutes.

It seems that when I add nutes the EC goes up and I am finding it impossible to hit target numbers on the EC while hitting target number with PPM. It’s either I go low on Nutes to hit EC or it just won’t happen.

Are there any tricks I can use to lower my EC while maintaining proper PPM for my stage of growth?

I am doing DWC.

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EC is a Calculation of PPM…PPM is one of two standard scales 500 or 700. Just Use EC its universal. I can get you the calculations if you want to make life difficult.

  • EC = Electrical Conductivity.
  • PPM = Parts Per Million.
  • TDS = Total Dissolved Solids.
  • All meters/pens measure EC. …
  • EC X 700 = PPM 700; Example: 1.00 EC = 700 ppm.
  • Or 1.3 EC x 700 = 910 ppm.
  • EC X 500 = TDS (or PPM 500); Example: 1.00 EC = 500 ppm.
  • Or 1.3 EC x 500 = 650 ppm.
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Shows how much I know. Can I just hit target ppm? In their week the ppm is around 1000 I am doing around 800 because that seems hot. But my EC is reading like 2.43.

Where it supposed to be around 1.2 or something.

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Yes, you just need to know which scale you are functioning on.
2.43 x 500 = 1215ppm
2.43 x 700 = 1700ppm
…Measure just your water source no nutes…mine is 300 this time of year. If I subtracted my water alkalinity I’d be 900 or 1400…If you’re using RO…just add more water, that’ll dilute your mix. So will tap/well but it always has that carbonate/bicarbonate component.

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Its a TDS so its 500 scale…Why is that LED segment on the 1 out, did you send it in the drink? If so, buy a new one, those are not waterproof - one dunk and done.

So 610/500 = 1.2 EC… thats cool.
In all honesty I’d be feeding harder than that, but I’ve been at this a while and I dont know squat about your exp. or setup.

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