Ppm,tds,ec help

can anyone help me out here my ppm readings for my ro dont make sense to me ppm of 3520??? and ec of 7130??? my numbers are way different than anything i can find probably operator error of some sort but any help and advice would be much appreciated!

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It may be a “scale” problem, check what “scale” your meter is set to.

@Audiofreak PPM (F) and EC (us/cm…F)

@Audiofreak Just used same meters and scale selection to test my 1Gal distilled w/ 1/2 TBL unsulphured blackstrap molasses and reading were as follows; PH(6.10) PPM(140) EC(324 @66.7F) now this is not RO measures this is Pre Intake

Those last readings may be right as RO water (I believe reads virtually 0 )

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If it were me I’d run my TDS meter through some Standard Reference Solution to be sure it’s reading correctly.


If your running your tap through your Reverse Osmosis system and your getting those numbers either the RO filters have failed …need replaced or your meter is out of whack.
Test some tap water and see what that is. Test some distilled water if you have it etc…RO water when the unit is functioning properly should be under 50ppm (EC of .1) and distilled should basically be zero ppm.
Taps ppm range varies and could be 100ppm or 500ppm etc.
I use the EC measurement as there are no conversions being done which the Ppm reading uses the EC and mathematically converts to PPM using a 50% or 70% of the EC.


@Myfriendis410 referencing solution?



@Skydiver I apologize if my acronyms are off but by RO I mean RunOff from my plants …I currently dont have a Reverse Osmosis filtering setup

Ok lol so your worried about the run off ppm.
I’ve had numbers that high with living soil growing organically and I’m not concerned with those numbers as the over watering…run off is leaching nutrients from the soil and it collects in the saucer. If your cleaning the saucers after each ruin off than each check will show what’s coming out. If you don’t rinse off the saucer each time the residue will build up and your readings won’t be accurate as it’s also including previous solids and will add to what’s really being flushed out.

So what is your soil being used?
What nutrients are you using?
What stage are your plants in…age…veg…flower etc?..
What is your tap water PPM


Yeah, somethings up with that meter. Even if it were on the 700 scale the ec would only be about 5.0

Soil: FoxFarm Ocean floor

Runoffs of 3000+ are pretty normal for ocean forest. Especially if it’s still fresh.


I haven’t added any Nutrients other than 1 1/2tsp of grow big(FoxFarm) mixed into 1 gallon Distilled on 3/21/20 and tested solution prior to administering and reading were as follows; 860ppm@69.F and PH 5.39. I also conducted soil test on 3/21/20 prior to feeding results; 6.0-6.5 range using soil test kit.

I grew them from seed and they are on 18/6 veg schedule these are just random bag seeds so have no clue strain ect.

@Skydiver just tested my tap(havent used for my plants yet) ppm(253@68 PH(7.10)

Those plants look very healthy.
Your tap isn’t too bad at all with those readings.

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I have same issues here and I even tested my pH meter and PPM meter and it’s fine. That’s if I did it right

@Skydiver Thank you I truly love this sh**…I have a question for you have you ever had a Plant skip its 3 sets? The two plants in gray pots seem to be identical except for the one on the right totally skipped her 3 sets and went straight to her 5s…