EC and PPM readings are wonky

FFO soil and FF nutes ( Big bloom , Grow big , Tiger bloom ) … I dont give nutes every time I water … 4th week of flower … 8/28/19 was the last time nutes were added and the PPM and EC were fine according to the room … Skipped adding nutes the last water and added nutes today … 9/3 … ( Before ) PPM / 1786 … EC / 3500 … Runoff was PPM/ 1900 … But the EC was 7372 !!! WTF ???

Double-check your meter is working properly.


Its brand new ,used it 4 times , new battery , washed the prongs twice , and checked 3 times , Not an expensive meter tho … As long as its reading the the PPM correct , should I just ignore the screwed up EC reading ?

Your meter is off. You cannot have an EC of 7,000. Unless measuring your concrete sidewalk haha.

Probably ought to check calibration.


I would get me a standard conductivity solution and check meter. And at that point if it’s off zero with distilled water then spanned with solution .

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I wish people would stop posting that EC, Hanna, eating, truffle post … I have no idea what it means and no one will just tell me … Hey your using this meter, and going by your FF feeding scale use this line to check your results , lol , And as you can see , the meter reads up to 9999 … :rofl::rofl:

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It was for demonstration purposes only; to show that the numbers are in fact incompatible and likely way off.

To get an EC value, multiply the ppm reading by 2 and divide by 1000.

Thus, if your EC is 1:

1*1000/2= 500 ppm.

And if your ppm is 500:

500*2/1000= 1 EC

Based on that your EC is 3.5


Every meter is different. We don’t know which meter you have, we may not be able to find any information on it even if we did. If yours came with a manual you should check it out for explanation or look around online to figure out what the numbers it gives you mean.


Sweet , I can do that … So right now, its .3 over the range it should be … According to the feeding schedule , the next 3 weeks it deletes the " Grow Big " nute … This should fix the issue right ??

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Yeah the ppm vs ec stuff is confusing. Had alot of issue with this still probably will and I have a good

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Only being my 2nd grow, Its like trying to learn a new language at 50 years old , lol … Back in the day, we just got some black soil , watered them and put em on the roof for sunlight … When the buds appeared , you hung it upside down in the carport and then smoked it … :grin::grin:


What I had started to point out is FF has VERY HIGH TDS levels compared to almost anyone else. They are having you mix nutes at DOUBLE the TDS I use with my plants. Using their grow schedule as recommended will almost certainly burn plants. The highest value I would try for in flower (and it’s all dependent on how the plant reacts) is around 1,200 ppm.


@bluethumb yeah but all the attention and spoiling is the difference between dank high end buds and bag weed. I hear tho it’s all down to science now. I’ve never used ff but I agree with @Myfriendis410 I would tread lightly on what doses they are telling ya. My medium has no nutes and I’ve learnt to use less than what they say.

Measuring TDS, then doing math to ascertain EC is about like measuring voltage and current, and then doing the math to get the resistance of a circuit, when you have an ohmmeter in your hand. The meter reads EC, then converts it to everything else it will display. There’s no point in the math when the meter is capable of displaying what your end result is.

Loop quantum gravity, by contrast, is concerned less with the matter that inhabits space-time than with the quantum properties of space-time itself. In loop quantum gravity, or LQG, space-time is a network. The smooth background of Einstein’s theory of gravity is replaced by nodes and links to which quantum properties are assigned. In this way, space is built up of discrete chunks. LQG is in large part a study of these chunks.

This approach has long been thought incompatible with string theory. Indeed, the conceptual differences are obvious and profound. For starters, LQG studies bits of space-time, whereas string theory investigates the behavior of objects within space-time. Specific technical problems separate the fields. String theory requires that space-time have 10 dimensions; LQG doesn’t work in higher dimensions. String theory also implies the existence of supersymmetry, in which all known particles have yet-undiscovered partners. Supersymmetry isn’t a feature of LQG.

Okay. But what do LQG and string theory have to do with anything? lol

It doesnt bro … I have been studying Loop Quantum Gravity for years … For me the absence of experimental evidence for either string theory or LQG, mathematical proof that the two are in fact opposite sides of the same coin would bolster the argument that physicists are progressing toward the correct theory of everything. I can understand it in the charts above … Your charts are all Greek to me , lmao … Are you familiar with String Theory bro ??

Very, very vaguely.

You could just use ppm and skip figuring out EC. :woman_shrugging: PPM’s tell you what you need to know, unless there’s a reason you need both?

But that was my point. Skipping all the math and charts would be to use EC. That’s what the meter is measuring. TDS is an estimate made from the EC measurement. Where it gets confusing is ppm, because different meters use different math to get their number of ppm.