High and Fluctuating EC and PPM For Dummies

So I have a giant plant growing in a 10 gallon container in a mix of Happy Frog and Ocean Forest.

First time working in such a large container.

Because of the weight of a soaked 10 gallon container and plans it’s hard to move around so I’ve been watering to runoff but have not been following the 20% protocol. It gets watered every other day as needed and I put about two gallons in each time. I’d say I get more like 5 to 10% runoff?

Here’s my problem, I’m entering almost the 2 month mark of flowering since switching to 12/12 and I’m starting to notice what looks like nutrient deficiencies due to Salt buildup.

Keep in mind I’ve only ran Florakleen through my pot one time and I think that was about 2 gallons as well.

Last night I ran 4 gallons water mixed with Florakleen and getting a bunch of wacky readouts when it comes to water runoff

I collect runoff and it’ll be around 1.7 EC. But then the next 2 gallons i put in, same thing with the Florakleen it comes out 2.2 EC.

And the PPMS are behaving the same way.

Within one night of flushing with FloraKleen (4 gallons water, 4 ML of Florakleen the PPM levels go as follows.


Should they be steadily going down?

I read online that there’s a certain way you need to mix your nutrients in order for it not to create a chemical reaction that creates basically salt. Does anybody know what that is? And can anybody help with my EC / PPM problem?

Up until now ive had NO PROBLEMS AT ALL with this plant. Now im starting to see tip burnage and discoloration in some of the leaves.

From the research I’ve done, all the symptoms all the symptoms I’m experiencing experiencing are due to a high salt content. Everything from leaves curling up, tips starting to burn, brown spots.

Another thing I should mention, and I don’t know why this is either, but every time I water I make sure to put in 6.0 water. My runoff is always always higher. It seems to want to stay at 7. Last night I watered at 6.0 came out 6.4. Second watering of the night for flushing purposes, water went in at 6.0, came out at 6.6.

Can anybody tell me what the hell is going on here, and how to fix this.

I should have only about 2 weeks left until Harvest but I don’t want to delay or stunt their growth potentially any more than I might have already have.


Just confirming that you’re not watering with a nutrient solution. The only things you’re adding to the bagged soil are water and florakleen, right?


Once @Nicky (tagging you alot tonight) said to stir in silica 1st then add & stir in cal-mag & then nutes. I forgot to once & noticed that it fromed crystals right away between the silica & cal-mag. sorry I can’t answer about the PPM don’t know enough about soil growning yet to give a good answer.

1 Like

Now yes. Was using Fox Farm Nutes including a salt based “bloom booster”. Once i saw the burnt tips i studied the run off which was all over the place. Now its just water mixed with Florakleen.

Its OK @pillsbury. If you think of anything let me know.

1 Like

Seems like that’s relevant and worth mentioning.

You’re just going to have to ride it out.

The problem with fertigation in soil (as opposed to soilless) is that it’s unpredictable. Because the nutrients with be adsorbed and absorbed by the soil particles, we cannot predict what’s actually going to be plant-available.

My suggestion is that next time use water only for the entire grow. You started off with an entirely adequate soil (assuming it was a core of happy frog and an outer layer of ocean forest). 10 gallons is good. Also, water just to runoff, not beyond that. The only thing I’d add would be a few drops per gallon of Dr. Bronner’s.


Go soilless in an inert medium like coco or ProMix, and fertigate.

1 Like

Yes core happy frog outer ocean forest. Just water? I’m sure youre aware that after 3 weeks happy frog (and i believe Ocean Forest) depletes all of its nutes therefore requiring more to be added. How would i go about fertilizing?

1 Like

Like, Pro-Mix, The stuff they sell at home depot? Whats the difference can you tell me? Ive read alot of posts were people stated they were using Promix. And what exactly do you mean when you say “fertigate”? I ran a lookup and not to sure i understand the difference between that and fertilizing.

Thank you

1 Like

They sell a “Happy Frog Fertilizer” that you top layer and its supposed to feed the plants for up to a month a believe. A one-and-done type situation. I was thinking about doing this prior to flowering that way I didn’t have to mess with mixing I need fertilizer solution.

Have you ever experimented with products like that?

1 Like

Correction. It was Happy Frog, Ocean Forest, and about 1/3 perlite.

1 Like

Yes, I’m aware the people say that. It’s observably false. I flowered for 10 weeks in a soil mixture of happy frog, ocean forest, additional dry amendments, and microbial life. A living soil. The microbiology makes nutrients plant available over time. For more info, check out Jeff Lowenfels’s books and podcast appearances.

My HD doesn’t carry it, and I’ve seen other people post a miracle gro bagged product called “pro-mix.” That’s not ProMix, AFAIK.
I buy ProMix in 3.2cft compressed bales. It’s a mostly inert medium of sphagnum peat moss and perlite. It has a tiny bit of dry amendments, but those are so mobile they’re washed out quickly.
You treat ProMix like a hydroponic medium. You water it to 25% runoff, but on a schedule closer to soil than coco.
If you want to use synthetic nutrients (and by all means, have at it) I advise you to stick to an inert medium like this. Coco coir is another option. And there are many others but are mostly truly hydroponic systems at that point.

I’ve top-dressed on occasion. Nitrogen is so mobile, it can wash out of your soil if you overwater. It can be hard to keep up with a demanding plant. But honestly I’d rather just give the plants bigger containers if prior runs seem to turn out deficiencies.

Fertigation is watering with soluble fertilizers.

1 Like

That would require a res and a pump and all that if i switched to coco coir no?

Im in the process of running a slurry test from the bottom of the root zone.

Have you ever done this before? If so, is it essential to ring out the soil and water mix through a paper coffee filter?

No, you can get by hand-watering. A 5 gallon bucket will suffice as a reservoir in many cases, whether you hand-water or automate. You can automate, and that isn’t very expensive. At least it doesn’t have to be expensive.

I was so frustrated by coco at first, but now I think it’s the best medium for me. But I like some things about ProMix. I use ProMix HP, but I’ve also had to use ProMix BX and it was fine.


I don’t understand what a slurry test (for ppm) is meant to tell you.

I should mention, your plants look fine. At six weeks into flower it’s hardly unusual to seen fan leaves start to senesce. The plants will move mobile nutrients from older fan leaves to newer growth. To the extent that the plants may have some minor deficiencies, you’re more likely to cause harm trying to remedy them than you are to actually “fix” them.

Ill have to look into that

I dont know much about slurry tests. I thought it was a more accurate way of checking PH/PPM/EC than simply checking the water runoff.