Newbie with PPM question

My ppm out of the tap is around 115. Is that considered a high or low or good reading? Also after adding nutes where should I want my PPM to be? Trying to learn and understand this PPM stuff.


that’s a very workable ppm for water, my well water is 90 out of the tap…one question is what makes up that 115 ppm, what minerals are dissolved in the water…whoever supplies you the water should have a report available of what’s in it.

if it’s well water, how do plants grow for you in general when you use your water on them?

1 Like

Mine is 164 and I consider that okay for town water. Rainwater is 3 for me (off the roof).

Some nutrient companies will list what they expect your PPM or EC to be. You can try checking there.

1 Like

hi guys. @markaas74 @kabongster I’m like 380 out of the tap. I wanna say most muni systems have to be under 450 ish

Many of the nutrient manufacturers will give TDS PPM or EC ratings on their feeding charts sothat you can give the proper dosage. Normally you add nutrients per their chart and then measure your runoff to be sure it is within their recommended range. A good example is on the FoxFarms nutrients chart (not an endorsement, lol)

In terms of Total Dissolved Solids (TDS), in the U.S., the Environmental Protection Agency (EPA) advises against consuming water containing more than 500mg/liter, otherwise known as 500 parts per million (ppm) of TDS, although many health specialists believe that ideal drinking water should be under 50 ppm or lower.


I see a ppm of 2000+ recommended by so many nutrient companies…it seems like yesterday I was starting with a ppm of 250 as a first feeding, going up to 400 then 800 ending veg, and flowering working up 100 ppm a week from that to 1250 to a maximum of 1500-1600 if needed.

1 Like

@kabongster you know I am following the FF feeding chart but when I add the recommended dosage, I’m no where near the ppm that they list nor is my runoff. Are we supposed to add more nutrients to reach that ppm? I never did quite understand that…

1 Like

hmmm, my numbers are strong for the dose of General Hydroponics I use, my experience with Advanced Nutrients ppm was what they expected…your nutrients are shook and mixed?..maybe @Countryboyjvd1971 could weigh in, he’s using the series I think.

I found that out to be the same as well, the ppm they listed was higher usually then when I put the recommended parts in together

I guess I’m lucky as I get a 0 reading coming out of my faucet. I take my water as soon as it comes into the house. It’s town water and a fairly new system. I do Hydroponics and use the three General Hydroponics base nutrients along with liquid koolbloom. If I’m using just the three base nutrients with Liquid Koolbloom my PPM reading will be about the middle of the desired PPM range on the chart. When I start adding Cal-Mag or a sweetener the PPM rises to high forcing me to add water which deludes the other nutrients. Here’s the chart I use for my system which is a recirculating system. I always try to keep the PPM level in the middle of the scale or lower. They have different chart for different applications.

I’m going to need to catch up here
I feed ff nutes but truth be told haven’t checked my ppm at all this grow
And really don’t plan on checking unless I see a sign of an issue
The only thing I’m doing differently from schedule is feeding once a week I water twice then feed
Also I reduced my mix just a little To 4/5 strength
I read a post here about not worrying about run off. Unless you have an issue ?