My drain off on my plants are reading 4000ppm?

Hello everyone! I just watered 50ppm on two plants without nutrients and checked the drain off on them and both read around 4000ppm?

The plants are 1 month old today and I’m using pro mix soil with worm castings, and only fed nutrients twice now with 350ppm in both feedings every 2nd watering. Just doesn’t make sense why the run off is so high when my plants look very healthy.

Also my meter is brand new and used calibration solution to check the meter. Any ideas, thanks everyone

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Also the plants don’t need watering or feedings for atleast 6 days everytime in 1gallon pots. Is that normal for them to go that long?

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PPM–EC conversion Chart

Re-printed with Permission from Jorge Cervantes;

EC Hanna Eutech Truncheon CF
ms/cm 0.5 ppm 0.64 ppm 0.70 ppm 0
0.1 50 ppm 64 ppm 70 ppm 1
0.2 100 ppm 128 ppm 140 ppm 2
0.3 150 ppm 192 ppm 210 ppm 3
0.4 200 ppm 256 ppm 280 ppm 4
0.5 250 ppm 320 ppm 350 ppm 5
0.6 300 ppm 384 ppm 420 ppm 6
0.7 350 ppm 448 ppm 490 ppm 7
0.8 400 ppm 512 ppm 560 ppm 8
0.9 450 ppm 576 ppm 630 ppm 9
1.0 500 ppm 640 ppm 700 ppm 10
1.1 550 ppm 704 ppm 770 ppm 11
1.2 600 ppm 768 ppm 840 ppm 12
1.3 650 ppm 832 ppm 910 ppm 13
1.4 700 ppm 896 ppm 980 ppm 14
1.5 750 ppm 960 ppm 1050 ppm 15
1.6 800 ppm 1024 ppm 1120 ppm 16
1.7 850 ppm 1088 ppm 1190 ppm 17
1.8 900 ppm 1152 ppm 1260 ppm 18
1.9 950 ppm 1216 ppm 1330 ppm 19
2.0 1000 ppm 1280 ppm 1400 ppm 20
2.1 1050 ppm 1334 ppm 1470 ppm 21
2.2 1100 ppm 1408 ppm 1540 ppm 22
2.3 1150 ppm 1472 ppm 1610 ppm 23
2.4 1200 ppm 1536 ppm 1680 ppm 24
2.5 1250 ppm 1600 ppm 1750 ppm 25
2.6 1300 ppm 1664 ppm 1820 ppm 26
2.7 1350 ppm 1728 ppm 1890 ppm 27
2.8 1400 ppm 1792 ppm 1960 ppm 28
2.9 1450 ppm 1856 ppm 2030 ppm 29
3.0 1500 ppm 1920 ppm 2100 ppm 30
3.1 1550 ppm 1984 ppm 2170 ppm 31
3.2 1600 ppm 2048 ppm 2240 ppm 32

There are three conversion factors which various manufacturers use for displaying ppm’s…

USA 1 ms/cm (EC 1.0 or CF 10) = 500 ppm
European 1 ms/cm (EC 1.0 or CF 10) = 640 ppm
Australian 1 ms/cm (EC 1.0 or CF 10) = 700 ppm

For example,

Hanna, Milwaukee 1 ms/cm (EC 1.0 or CF 10) = 500 ppm
Eutech 1 ms/cm (EC 1.0 or CF 10) = 640 ppm
Truncheon 1 ms/cm (EC 1.0 or CF 10) = 700 ppm


I have more that I can give you and it’s large but a lot on PPM information that you should know.
you can copy and paste it to your files. I printed mine out and keep it in my grow room for reference.
Hell, here it is any way …

Knowing What Your Plants Are Eating and How Much They Can Handle
October 20, 2016 by Devin Martinez
One big question growers ask is “Why are my plants suffering even though
I used all the right nutrients, feeding cycles, lighting cycles, and adjusted
temperatures and conditions to their absolute best?”
That’s because their pH and PPM levels are off, making it difficult for your
plants to eat. pH refers to potential of Hydrogen ions in your water, which
will determine if your water is too acidic or has too much alkaline in it.
PPM (parts per million) refers to the concentration of minerals and soluble
matter in your watering solution.
Correct pH and PPM levels are the backbone of any grow, and will be the
difference between a healthy grow and a huge waste of time and money.
pH Levels
Simply put: the right pH level will create an environment where your plants
can absorb nutrients quickly and easily, leading to a better harvest.
Nutrient-rich water is filled with elements that are helpful to your plants.
However, if those elements can be broken down properly those same elements
can harm your plants.
pH levels is important to understand because the right level will determine
the quality of helpful bacteria in your water that help break down elements,
helping the metabolic rate of your plants. How? In two ways:?

When pH levels are too low (pH level of around 5 of lower), heavy
metals like iron and aluminum change and can become toxic to your plants ?

If the pH level is too high (pH level of around 6.5 or higher)
elements like calcium and phosphorus can’t be broken down completely, which
will hinder the growth of your plants
This change in properties is due to how acidic your water is or is not.
You’ll want your plants’ nutrients to be a little acidic otherwise they can’t
break down, but too much acidity and your nutrients can become toxic.
So remember: pH too low= toxic to your plants, too high= growth decrease.
That’s why you want to have the perfect level of acidity in your water,
which will be around 5.5-6.0
Typical pH Levels ?

3.5 and below: Root Damage ?

4.0-4.5: Poor Nutrient Uptake ?

5.0-5.4: Good pH Level ?

5.4-5.8: Perfect pH Level ?

6.0-7.0: Acceptable pH Balance ?

7.5-8.0: Poor Nutrient Uptake ?

8.5 and Above: Root Damage

Note: Soil grown plants tend to need a little bit higher of a pH than hydroponics
because soil retains and releases certain elements to your plants at different times.
However, both hydroponic and soil pH levels should stay within the same optimal range
of 5.5-6.0 pH.
PPM Levels
PPM (Parts Per Million) refers to concentration of the particulates in your feeding
From minerals found in tap water to natural elements found in your nutrients, your
job is to make sure that the PPM levels in your water solution are on point so you’re
not under- or over-feeding your plants. While it’s an easy concept to understand on
the surface, it’s a little more complicated when you have to adjust elements.
Now, pH plays a huge factor in PPM levels because even though you may have the correct
PPM reading, some of the particles- and the concentration of those particles- can be
harmful for your plants.
For example, let’s say your plants need to be at a PPM level of 700. You mix your
solution and you get a PPM reading of 700 but your pH is around 4.5. That means that
the majority of the available food for your plants is likely to have lots of heavy
metals in it, which will quickly toxify the plant. You’ll need to adjust the pH level
of your solution to make sure you’re not toxifying your plants.
“But won’t that throw my PPM levels off because you’re adding particles to your feeding
solution?” It can, and that’s what’s so tricky about PPM and pH levels: When you adjust
one you usually have to adjust the other, which can be simple or a huge pain depending
on the water and nutrients you’re feeding your plants.
Common PPM Readings
These readings reflect the PPM your water should have at a given stage of growth
? Seedlings: 100-250 (nutrients aren’t really needed here, hence there’s not a
lot of particles needed)
? First Half of Vegging Cycle: 300-400 (this is usually after you transplant,
which still don’t require many nutrients)
? Second Half of Vegging: 450-700 (you’ll start giving your plants more nutrients
at this stage)
? First Half of Flowering: 750-950 (your plants will be eating more as they grow,
so they’ll be taking in more nutrients)
? Second Half of Flowering: 1000-1600 (this is when your plant’s eating the most,
especially if you give it additives)
? End of Flower, Entering Harvest: As close to 0 as possible (this is when you’ll
be flushing your plants, so you don’t want there to be a lot of particles left over)
Adjusting pH Levels
When it comes to feeding plants there’s two ways of looking at it: homemade or store bought.
Same goes with balancing your pH: you can either purchase a pH buffer from a store or you
can use ingredients you can find around your home or in the grocery store– but both come
with their advantages and disadvantages.
Homemade pH Buffers
? Advantage: If pH levels are low you can use a little citric acid or even white
vinegar to help bring your water’s pH down. When you need to raise your pH levels you
can use a little bit of baking soda in your solution and bring those readings back up.
This will cost you less than picking up a buffering solution.
? Disadvantage: The issue with using these solutions is that they don’t work for
very long. You’ll find yourself having to add a little lemon juice every other day, then
having to use a little baking soda to even things out. Moreover, we’ve also heard of
growers using these ingredients and seeing severe spikes in pH, which if not handled
properly and quickly and bring your grow to a halt.
Premade pH Buffers
? Advantage: Most hydroponic companies out there will have pH buffers, usually
called . They’re much easier to use than citric acid or white vinegar mixes. They’re
designed raise and lower the pH of your water while keeping your water’s pH levels
balanced for longer than it would be without them.
? Disadvantage: As we’ve always mentioned, easier usually means more expensive.
These solutions usually won’t cost you an arm and a leg, but they’re definitely something
you can’t simply make at home and will cost some money.
Adjusting PPM Levels
Before you start adjusting your PPM levels, you’ll first want to make sure your tap water
is ready to feed your plants. That means you’ll want to adjust the PPM of your base water
before you start feeding it to your plants Now, any time you add anything in to your watering
solution, you’ll be adding more particles in to it, so keep an eye out on your PPM levels at
all times.
? To rid your water of too many particles you can use things like a carbon filter or a
reverse osmosis machine to clean your water. However, many growers agree that most tap water
has helpful minerals (like calcium and magnesium) that actually help plants.
? During and after the vegging stage, your plants will want more out of their feedings
so filtering isn’t really necessary. That’s why we recommend only using filters at the
beginning of the plants life when low PPM readings are needed
? For a quick fix when PPM’s are high just add a bit of fresh water with a good pH
level and watch them drop. Filtered, pH’ed water is great when things get a little too
much in your reservoirs.
? When readings are low it’s usually time to feed your plants. When you add nutrients
to your feeding solution your PPM’s will go back up, and when your PPM’s and pH’s are in
balance your plants are going to be happy and healthy.
? Just remember that these readings need constant adjustment, so if you haven’t been
keeping a close eye on your plant’s PPM and pH levels there’s not better time to start than now.


4000 PPM ??? Something very wrong.

4000 PPM will kill

One gallon pot is too small. 3 gallon for auto’s. 5 gallon for regular.


I’ve been where you are, you are damaging your plants with that high ppm. They may not show it too bad now, but mine got real stressed as they moved into flower. Get them into a 5 gallon pot like @tanlover says and into fresh soil. Water at 6.5 pH without any new nutes for the time being.

When you transplant, they may be a bit rooted so you may want to loosen the root ball a bit when you transfer.

Are you mixing in worm castings with the promix when you make your soil?


Ya I mix 1/3 worm casting into pro mix soil. And here’s a pick of one of them in their pots.

What was your last run-off reading before this? They are one month old, but you’ve already fed them twice? When you started feeding, were their cotyledons dead?

With unamended Promix, you have to start feeding within about 14 days of putting them in the medium. With your worm castings/promix blend, you probably could have held off feeding for several weeks. That’s what that high ppm reading is telling you: there’s already enough stuff in here, don’t add more until this number starts going down.


yes 5-7 days between watering is normal and u r doing great by waiting until they need water again.!!

i know everyone says to transplant, but i suggest waiting to transplant until the plant looks as big or bigger then the pot, at one month old in a one gallon pot they r not ready to pot up.!
u can also judge when they r ready to transplant when they need watered every other day or daily.!

they look good so just keep on watering like u r doing just do not add any ferts for now.!

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I have a ? What if my ph with nutes is 6.56 and my run off ph is 6.21. How far off or close to getting this shit right. Thank you for your response…:sweat::thinking::sweat_smile::pray::v:

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6.2 is on the low side of soil and high side of soilless/hydro. What’s your medium? @smellthat

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I use composted soil.

I wouldn’t worry about it too much.
Next watering, you can go like 6.6 or 6.7pH and see if it perks up a bit. @smellthat

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Thank you ! I am relieved. :+1::v::sunglasses:

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Are all these PPM readings at run off? My last reading was 4500 (runoff) and that was a collective reading of four 7 gallon pots. So yes next couple watering will be pH d water only till I get maybe 1800 ppm runoff. just ending my 4th week here of growth. My last feed (prior to the one 8m reporting on) from reservoir (two 5 gallon buckets) was at 800ppm. This current, recent, watering that I’m concerned about was with some Silica … kinda wished I measured that before using … duh … did 1/3 teaspoon per gallon mix so still should not be that high of a ppm. pH was at 5.8… the runoff at 6.8… lot of info here…almost confused myself writing this…hope this makes sense. thoughts?

Hi garrigan62 I have a big problem I’m in week 3 of flowering stage and my plants are at 4000 ppm in the 5gallon pot I don’t know what to do I’m really worried here but everything looks normal though I’m so stressed :tired_face:


Your plant’s are lookin good my friend , I wouldn’t stress too much just yet…
Next time just water only with a good ph for your media and see what the numbers are…
Unfortunately @garrigan62 is no longer with us…
His freindship and wealth of knowledge is missed every day… rip :pray:
If you have a journal going , throw out a tag…
I stop by…
:v: :sunglasses:


Oh my goodness thank you very much for your help peachfuzz I am sorry to hear about this, I just joined this great ILGM and he was the first person I felt I should to ask help with my issue may he Rest In Peace :pray:t4:


Just tag anyone like you did him and someone will chime in… :+1:
He was a good guy and helped alot of people…
For some reason , we always loose the good ones…
:v: :sunglasses:


I totally agree with you, we always lose the good ones and absolutely that’s why I went to hm first for help he seemed very helpful, do you know how he past away ? peachfuzz