Great information Lefty, thanks for sharing.
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Was thinking about mixing up a batch of the PP delux to try to hit the elemental values suggested but, I don’t have the cal prime, the poly phosphate, or mg nitrate. I’ll try to come close using what I have but, I know it won’t be the same.
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You should be a little careful. The “PP” or polyphosphate is safer to use in high levels compared to orthophosphate. The calcium nitrate in the recipe isn’t cal prime, so no worries there. Magnesium nitrate can probably be substituted 1:1 with epsom for a slight loss of nitrate with a slightly raised sulfate. It might be worth reformulating in hydrobuddy with the nutrients you do have.
I hope that giving a few recipes with explanations will help demystify mixing from scratch, to give people a starting point and a short list of nutrients to acquire, and show that it is flexible and highly customizable. Plus it’s fun 
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Dude, when did you level up, I missed it!
Cheers
G
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A little update to make here – I am currently thinking that the plant prod chelated micronutrient mix might be a little light in zinc. A more optimal amount is probably about 2x what they provide. I am going to try a split using Peters STEM of about 35g plant prod, 5g STEM.
STEM is a weird micronutrient mix. I’m not sure what its intended purpose is, but it has a bizarre balance of micros. Anyway, it’s zinc is disproportionately high, so it actually works out pretty well in this case.
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Tomato Recipe Experiment
These tomato recipes trip me out, but I’m going to experiment with similar targets and see how it goes. I think cannabis and tomatoes share a love of calcium that is not normally reflected in other formulas. Interestingly, they use a pretty low amount of N during veg.
Secondly – what they consider to be ‘low’ calcium (144ppm) is very high in comparison to what off the shelf formulas provide. High calcium and low nitrogen is difficult, and they accomplish it by using calcium chloride. I’ve always been wary of CaCl2 – chlorine isn’t needed in high amounts. But if I want to get calcium up that high, I’m going to have to use it.
Here’s what I’ve settled on for “stage 1” – a bit more P and N and less Cl. I’ve replaced the MKP with grow clean for the polyphosphate and higher K ratio.
Here’s the 250gal amounts:
These formulas are fairly simple in some ways. They keep P, Mg and the micronutrients fixed for the entire grow, while N, K and Ca are gradually raised.
That means that I can start with this base mix, and increase CalPrime, calcium chloride, potassium nitrate and potassium sulfate in the next stages of the grow. I’m a little uncertain about the high levels of nitrogen toward the end of the grow, but we’ll just see how it goes.
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That was the inside joke on using the code-word ‘Tomato’ to reference Cannabis…
…Back in the 'ol days…
Cannabis nutriment requirements closely mirror Tomatoes, especially the Calcium. I think you are correct about the late flower Nitrogen though.
Cheers
G
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Way over my head in here but I can appreciate what your doing here. 
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I’ve heard that from time to time. Ever wonder how closely? That’s what I intend to find out 
Tomatoes are far better studied than cannabis, so I guess if they have similar requirements, then maybe we should be starting with their recipes. 
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Would Calcium Acetate be an option? I’m trying to figure out what to use to keep my Ca levels high while dropping N. I’ve been using Calcium EDTA but, keep it to a max of .5 a gallon. Was using way to much last run and it was causing antagonization issues with all the other elements. Someone on another forum set me right about the problems it causes in a hydroponic setting.
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Did this thread ever just take me down memory lane lol
I grew up with a guy whos dad use to have a basement full of plants. Still to this day some of the nicest plants and bud I have ever seen. Anyway he took one of his dads grow journals one time and it had a ton of stuff in it about him mixing his own base salts with a shit ton of numbers that at 13 I had no idea wtf they meant lol
Anyway it always gave him mad scientist status to us . Goodluck with your venture 
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I haven’t looked into calcium acetate for hydro, but I had a similar experience with the EDTA. It doesn’t work well… too many other interactions and maybe too much sodium? I think the other option I would consider if calcium glucoheptonate, because I’ve seen that in some formulas. But it’s liquid, fairly expensive and low density. So I’ll see how the chloride does first. I’ve read about people using it at around .5g/gal and having good results. So if I stay under that, it might be ok.
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I’ve heard of others using the Calcium Gluconate with decent results. Some of the commercial operators I’ve spoke with recommended using the chloride at .25 per gallon to try and keep chloride under 40 ppm.
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Thanks, that’s really helpful. I think that’s the number I’ll target then and see if I can make up more calcium elsewhere. I know that 190ppm N in late flower is not going to be optimal, so I think it’s going to become a choice of more Ca or less N.
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Definitely want the more Ca in late flower. I think if you go the gluconate route to make up the extra Ca, you’ll be good to go.
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I think I’ll give it a try. I have some of this stuff:
When K hits high values (350ppm) I can probably make up about 25ppm of Ca using that and 25ppm from the CaCl2. I’d like to keep N at ~150ppm, and I think with those Ca can still hit 200ppm.
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Here’s a fairly unusual take on micronutrients:
https://www.cannabisbusinesstimes.com/article/cultivation-matters-ncsu-boron-fertilization-nutrition-deficiency-toxicity/
https://www.cannabisbusinesstimes.com/article/when-micronutrients-become-macro-problems/
Everything is normal, except… 8.5-10ppm Boron. What the?! “Normal” fertilizers apply like 0.5ppm Boron. Anybody ever heard of this?
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I am admittedly a micronutrient dummy. Have a sack of TM7 but yet to make use of it.
For comparison I see Bioag’s TM-7 contains .37% Boron.
Is that approx .9775? PPM
Searching around, several sites talk about higher than 2ppm being risky.
.2 ppm risky on the low end.
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Peters STEM, Plant Prod Chelated Micros and Jacks MOST all have ~1.3% Boron. At least for the plant prod, their recommended rates come out to about 0.5ppm – which is what I’m used to seeing.
The recommendation from that site is just way higher than anything I’ve ever seen.
On that note, I think I understand how to use the Peters STEM. It’s separated from the Iron DPTA so that it can be tank mixed separately.
On that tomato page, they show this for tank 1:
and this for tank 2:
So the iron gets tank mixed with the Ca, while the rest get mixed with the sulfates/phosphates.
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I love it for foliar spray any time prior to bud onset. There’s a few insoluble bits, so I don’t mix it in my reservoirs. But it’s great for my purposes as a foliar feed.
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