Adding dolomite to Happy Frog

Hi everyone, starting to set up for my next grow.

I have Happy frog soil and after alot of trouble with first grow im trying to cover my bases

I did a slurry test on the soil and instead of being the 6.3-6.5 ph I thought it would be it’s just over 5.7 and 680ppm. I want to add dolomite, I think, to bring it up to 6.4 or so… any idea on how much that would take for 2cu ft.

I did see an article that said 1lb of limestone will raise ph in 2cu ft 2 full points (5.0-7.0).

Should I just do the math from that or is there a better way.

I’m assuming I would just add it to dry soil and mix and then do another slurry. Is that the procedure I should be doing?

Had major ph problems first grow

Here’s my info

  • What strain Girlscout auto and gorilla glue auto

  • Seed bank ILGM

  • Method: Organic soil, FF Happy Frog

  • Vessels: 3 gallon bags

  • PH of Water, Solution, runoff: planning on maintaining 6.4ph throughout

  • PPM/TDS: starting new Happy frog it was 680ppm

  • Indoor 5x5 tent

  • Light system : spider farmer sf4000

  • Temps; ave 72°f

  • Humidity; varies… low 30 high 62

  • Ventilation system; Yes 6" with inline fans 390cu ft/min

  • Co2; No, but considering getting a bag or bucket

I’d start with 4 oz or so, allow to percolate into the medium before testing PH.

This is a waste of time and money for a number of reasons.


Keep in mind that dolomite is calcium and magnesium carbonate so you may want to cut out any calcium or magnesium extras (cal mag, epsom salt) from your nutrient routine or you could end up with an excess of one or both.


Thanks for a good place to start… sounds about right. Im not sure what you mean about percolate or how long

Yeah, the more I hear about the co2 containers the less im interested. Most say the same as you

Great point, Thank you! I had kinda noticed that lol… Im planning on using jacks 321 so maybe I should just get regular crushed limestone. No extra minerals there?

May just need to lower the cal nitrate and epsom salt amounts if you really plan on adding in dolomite. But a runoff for ocean forest is typically around 5.8 for me. It was when I would try and correct that when I’d start to run into issues. Just letting the soil do it’s thing and there weren’t any issues.


I like the way you think :laughing: Thanks!! so just add 6.5 water and keep an eye on runoff? I need to empty the bag into my garbage/mix can and mix up well too

Do many people bubble their water in jugs? Or is just letting them set open is enough. Im 7.3ph at tap but 8.3 after bubbling 24 hrs. I’d rather not have to add so much ph down

Yep, I just add nute solution at 6.5 and let the soil do its thing. The runoff is almost always 5.8. I only bubble while I’m adding in nutrients. My tap is 7.4 and after mixing jacks it nails it at 6.52 so I don’t need to add any ph adjusters.


That will grow cannabis just fine.


Perfect, sounds great. Thanks for your help. Our growing environment sounds pretty similar

It will be my first time with jack’s. Having high hopes

It’s really that simple. You can mix part A and epsom together. Just make sure it’s fully dissolved before adding the cal nitrate. The cal nitrate and epsom can react and bond to form gypsum if the epsom isn’t fully dissolved. I usually throw in the part A and epsom the day before I need to feed. Then I’ll add the part B the day I feed.

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Great advice, I’ll add the day before. I was wondering how long it took the first to dissolve

I was thinking about weighing out a couple weeks worth of the 3 parts and storing them in those little plastic condiment containers for convenience, also I need to count on my wife for a few feedings but she wants nothing to do with weighing it :rofl: Do you think part A and epsom could be stored like that combined?

Do you use jack’s with FFOF? If so when do you start with jacks? Do you use it full strength?

I used to use ocean forest but I’ve been using big rootz soil for a few grows now. It’s basically ocean forest but seedlings do really well in it. I wait until the soil runoff gets down to around 1000 before feeding. Then I go full strength.

I weighed it for the first 4 weeks I used the stuff and got tired of that so used a teaspoon set to figure out how much of each. For part A it took about 7/8ths of a teaspoon (so nearly full teaspoon). For part B it was 1/2 teaspoon. For epsom it was 1/4 teaspoon.


I’ll check again after I mix the bag up, but first slurry test was 680ppm unless I read it wrong. I was thinking 4 weeks or 5 unless I see a deficiency. Good to know you can start out full strength

Yeah there was an issue with the slurry test. Should be above 2000

Anyone can say all they want about adding co2 bags or buckets. If u can afford one to try get it and try whats the worst that can happen either it helps or it dont. U did a grow without it now do one with it and add ur opinion about the co2 theory here. Any kind of xtra co2 for the pla ts will be a benefit but is it really worth the money is the key. I dont really know myself but watching videos and reading about it from pro ppl online who use them say its not alot of help but they do emit co2 to the area and it does help some. And some is better than none. So if u habe the means to get it and try it go for it. Most that will happen is the crop will lopk the sane as the crop without the bag.

Haha, my first grow was a disaster. Hopefully my next grow does well. Then I would have a fair comparison maybe for a 3rd grow with co2, but I don’t have money to waste, so idk

Considering a 10x10 tent so my wife and her best friend could sit in it and just do what they normally do. They’d have it up to 1400ppm in a 1/2hr. They never shut up :rofl: :rofl:


i used dolomite lime in my garden due to very acid soil…

aparently it regulates the PH towards 7, where as lime on its own will just make it more basic…

you cant mess up the PH big time with dolomite, but with lime you can!

Thanks bud, im going to try and avoid using if possible

@bonger our set ups are very similar. When do you plan to start the next run? I’ll be dropping some gsc autos in the next few days

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