I need a beginners crash course in PPM

I just bought a PPM meter to up my game… this has probably been answered a million times in numerous threads, buuut I didn’t search, so let’s start fresh.

Who can give me a crash course on the basics of measuring the ppm of nutrients? My tap water measures in at 30 ppm and 7.0 ph.

Is there a process to follow? Like measure the ppm after each nutrient is added? Or a “goal” level for the final mix? I have zero…ZEEEROO idea or knowledge on this subject so any info is appreciated


What I’d do is mix how you’d done before and take a reading see what you actually have been feeding . Get a base read and adjust from there

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700 ppm is getting up there your meter is on the 500 scale did you calibrate it ?


ppm/ec/uS all it is the measurement of the conductivity of water, saying that different things in said water will be more or less conductive than one another, so will different nutrients brands type parts ect

but as recommended start with a value and level you know then work from there


Interesting I’ve never checked the ppm of just nutes
Are you talking about before you mix them with water

My tap water is 40ppm which I was told in the autoflower forum that a good number the ph is 7.9

If I’m just feeding water I put a little ph down in to drop it to about 6.8-6.5 ph

Maybe I’m doing it wrong myself lol


You’d want to mix your chemical then check the ppm and ph adjust to desired levels.


presume you ment 5.9

“popular knowledge” soil is more ideal at around a pH of 7 and hydro like environments around 6 , i run 6.2 myself at the moment.

Now saying that pH is different than EC, and a bunch of things come into play as to whats a good EC and pH that will work for you.

having meters for both is a worth while investment imo


Where can I find out what I should be aiming for…I measured existing nute mix at 260 ppm (seedling feed). Is there charts i need to follow, Google links I should read? Typically I go half recommended dose for seedlings and back dose for anything else .

Basically… im down to go into a Google worm hole of info I probably don’t need, I just need to know which way to go first lol


Should I measure say, 500ml of each specific nutrient to know its ppm, and rocket appliance equation that into the water for a diluted goal, or am I way off track

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if using multipart nutrients you would measure after mixing in each part , if its a one part well just the final value. that and knowing your starting value before nutrients is handy but a tap of 30ppm is nothing so you can more or less disregard it


260 is fine for veg depending the plants needs I feed on average 450 my tap is 260 mid veg 600 veg / flower 800/1000 depending how they feel do 2 feeds then a semi flush straight water then 2 more feeds


consider though that is with your brand/type of nutrients and your water, as a 600ppm of miracle grow vs a 600ppm of maxi gro is two completely different things and you should only compare values if the make up of the nutrients are the exactly the same.


I meant my water ppm is 40 and the water ph is 7.9


Good call depends on what chemical you use

Thats what im looking for… check after each nutrient is added. Im using a 3 part with a PGR (?) And soil microbes…

ahh gotcha yeah 40ppm is good, and 7.9ph tap is quite high

Soooo find a chart with “ideal” ppm of each main nutrient (n/p/k) and consider the rest as extra?

What you could do is follow there mixing instructions check the ppm and then adjust down by adding your 35 ppm water to get it to a safe lower number


But how do I know a “good ppm” is there a general level i need to know?

I just checked it ph is pretty high tonight