Is this Iow runoff pH?

I just watered my plants with 1/2 strength nutes pH adjusted to 6.3 and 690ppm and the runoff pH seemed really low. The three plants runoff measured 5.2, 5.3, and 5.6. These are about 7 weeks from breaking soil and transplanted about 2 weeks ago. Soil is a mix of mostly Fox Farms Ocean Forest with some perlite and coir mixed in. The plants look ok, maybe a tiny bit of yellow creeping in but might be imagining that.

Why so low runoff pH and what should I do to fix it if an issue? Thanks for any help!

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Foxfarm OF is notorious for really low Ph, so you’ve got to keep an eye on it and adjust as necessary. I suggest you do a flush using 7.0 ph water to get your Ph up to 6.3 minimum.



Yes it is important to know your run off ph. there is a reason why your ph is coming out almost a full 1.0 lower than its goin in. soil is too acidic. testing your runoff is just about the easiest way to test your soil ph. but the main question is how do your plants look? are they showing a ph problem? or any problem at all or do they look healthy? dolomite lime is what you should ammend your soil with to bring up the ph. it has a neutral ph. considering its like $10 i believe for a 40lb bag cost isnt an issue and it will last forever. i have ran into same issue with roots organic and after top dressing with the dolomite it eventually climbed its way back up.:

Whats your opinion on roots organic? Iv heard in other posts that you make your own super soil which I think im too much of a noob to be doing now but Im thinkn bout changing soils. I’m currently using happy frog but had issues with this grow and lookn for info on premade soils.


Yes I do and don’t cut your self off short. Making your own soil is very easy to do.
I thought the same thing at first, until I saw my results.

all you need is a few things to get started.

But first. The Seedling soil

MG potting soil only use te one that doesn’t feed for any months with a N P K OF 0.012 0.06 0.08 THESE ARE NOT THE NUMBERS BUT YOU GET THE PICTURE

2.) Worm casting lots of it seedling will love you for it. I use a lot
add more

Soil Recipe to be mixed with 1 to 1/1/2 cu ft of base soil

Pro Mix
Mushroom Compost and Black Cow Soil compost

.3125 lb or 5 oz Fishbone Meal 3-16-0

.3125 lb or 5 oz Steamed Bone Meal 2-14-0

.625 lb or 10 oz Bat Guano 0-7-0

.3125 lb or 5 oz Blood Meal 13-0-0

.3125 lb or 5 oz Feather Meal 12-0-0

.375 lb or 6 oz Colloidal Rock Phosphate 0-3-0

1 tbsp Potassium Sulfate 0-0-53

1 tbsp Souluble Kelp Powder 0-0-17

1 tbsp Mycorrhizal Fungi (300 spores per gram)

3/4 tsp Powdered Humic Acid (90 % pure)

1 1/2 tbsp Epsom Salt

1tbsp Sweet Lime (Dolomite)

1 tbsp Asomite (Trace Elements)

6.25 lbs Worm Castings



You plants look great!! Thanks for the info I really thinkn bout making my own soil now, do you add nutrients during the grow with this soil recipe? Or is there enough nutes in the soil to last the entire grow?

You got it. Only water. Well and some bio tea . I’LL get that for you here in a min or two.
One thing you must remember. Everthing with a high N and low P K makes your veg soil which goes in your pot last and everything with a high
P K and low N goes in first, that way when you transplant your seedlings their going into your veg soil and will grow into the flower soil.

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With this soil recipe when you refer to “ base soil”, you mean the promix, mushroom compost and black cow compost? If so what are your ratios?

Thanks for the help! I flushed them quite a bit but finally got the pH into the low 6s. I think they look OK @garrigan62 but the growth seemed to have slowed. Here they are this morning about an hour after lights out. Bottom right plant was not watered with the other 3 (it has now tho).

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Well now that your in the 6s you’ll have to give they some time to recoupe.

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I intend to transplant soon, I will be using the rest of the FFOF plus perlite and coir plus some Kellogg Organic Plus soil if I need any to fill all 4x of the 5.5 gal pots. How much dolomite should I add to that much soil?

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How about a top-dress of dolomite lime?

The coco will bring your PH down too FYI. Peat could be used to replace the coir.

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if using soil one tsp. spread around near the bottom and one more near the top with each adding you mix up the soil before moving on ok ?
and @Myfriendis410 is correct about the coco

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@garrigan62 @Myfriendis410
I just found/bought a bag of Happy frog and a bag of Roots Organics Original mix…and a small bag of dolomite. Having those plus about 2/3 bag Ocean Forest and almost a full bag of Kellogg Organic Plus and also plenty of coir and perlite; any suggestions of a good mixture? Layered with a different bottom layer? I’m hoping these 5.5gal pots will be the final pot.

Yes… you got to add a lot of worm castings to that Roots Organic soil Ocean Forest and that Kellogg Organic.
get some other soil that’s very low in N P K Like that Miracle Grow potting Mixit’s what I use. it will say on the back of the bag N = 0.06 P = 0.12 K = 0.4 and add a lot to that R O soil and Kellogg soil along with the worm castings and perite. This will help break down the N P K in thoughs soils and won’t harm your plants cause if you don’t your going to be posting pic’s of your plants asking, What’s happened to my plants

Which Miracle Gro potting mix? They have several and the original potting mix says it feeds for 6 months (which I had read to avoid). They do have a seed starting potting mix at .03-.03-.03 and also an Indoor potting mix but that one is .25-.13-.19.

I was trying to upload a pic of with type of MG but my battery went dead durning the upload lol
Sorry I didn’t notice the caps till just now

It really isn’t as hard to do as it sounds. I know for a fact that once you start doing this making your own, it won’t be long before you’ll be saying … Hey Will try this soil I came up with my last grow was off the scale… and i’m not fooling either my friend cause i’m hooked on coming up with different soil mix’s and they keep getting better the more I experiment with the different kinds of amenments.

This is what I mix with every watering from veg to flower but not the last two weeks of flower just water then.

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Cool, I’ll get some of that. Just curious, but is all the extra worm castings for the plants or for the microbes?