Thank you! This is many many times better than what I found! The only question is, since I don’t see the percentage formula on the package - is the drugstore product different from the agri-culture product wich is 9.7Mg12.8S for example?
Both the agricultural and drug store epsom salt are going to be magnesium sulfate heptahydrate and work the same in my experience
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I though you guys and especially @Rhai88 (Profile - Rhai88 - Overgrow.com) might like to see Jack’s “420” (4:2 Hydro/CalNit with no Epsom per GG and others) vs Athena’s Pro line @ week 5.
Caveat: the charts include my specific tap water (contributing some Ca and S) but you get the idea and can see the data.
Those running Jack’s have headroom for P, K, Ca, and S in flower.
Jack’s “420” blend compared to Athena Week 5 Flower:
Here’s a little “JackThena” blend compared to the same Athena Week 5 Flower:
I cheated by adding AgSil to the mix for K, but need the Si anyways.
Also tiny tidbit but I’ve noticed many recent comments and data suggesting boron is a fairly important, fairly under-provided micro. With Jack’s, all of the micros are in Part A (Hydro). It’s a 3-2-1 mix, or 3:3 Hydro:Else (or, 1:1 
) Bear with me I’m pretty tired, new baby in the house!!
The Jackthena is 5:4 though…which bumps it’s micro fraction my 1/5th. People SEE this in the results because Fe and B (and other micros) are now provided 2x over 5 waterings. This seems to matter quite a bit and isn’t often discussed as causal.
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Hey guys! I decided to try a 4:2:0.5 scheme from GG. I am now on day 10 of bloom and the same problem is progressing on more and more plants in my rdwc. New leaves are lighter than usual, yellow/lime in colour and smaller in size. My ec is 1.6, soft tap water.
From the charts on the Internet, it looks very much like a sulfur deficiency so I increased the amount of magnesium sulfate from 0.5 to 0.75 5 days ago but not sure it works. Do you have any ideas what is going on? Should I go back to 3/2/1? Although until I understand what’s causing this, I’m not sure it will help.
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It’s almost certainly not sulfur deficiency. The sufficiency limit for sulfur is extremely low. Normal amounts of magnesium sulfate or potassium sulfate used in most any fertilizer will have sulfur sufficiency. I think you would need less than 40ppm, while 321 has about 3x as much.
I would consider that you actually have P or K excess causing those problems. Especially in veg and early flowering, K requirements are very low, so a 4/2/.5 is probably not useful. P is useful early, because root development is substantial, especially going into stretch.
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I run full strength Jacks 321 from start to finish, no flush. I dry at 60/60 for 10-14 days and then cure for at least 30 days. You will never see black ash, popping, or the like from any of my cannabis.
Can you expand on this? You just keep topping off but never flush your bins/buckets? I did this with Advanced Nutrients Sensi PH Perfect before.
Do you have to PH Jack’s when you topoff?
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Has anyone else here been into some variations from the standard recipe?
I’ve tried 4 - 2 - 0.75 and 3.8 - 2.2 - 0.9 in bloom and to be honest I haven’t noticed much difference. Could it be that I was only making things worse by making the plants lack calcium?
All that’s on my mind right now is a feeling of excess nitrogen in the standard formula and an intuitive desire to reduce it during the flowering phase.
Maybe I’m wrong and this is an outdated concept?
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Thank you! I haven’t visited his channel in a while, priceless information as always.
The only thing that confused me about all this is the calcium is too high. He suggests 3.25 to 3.5g calnit at the beginning of flowering, which gives us 163 to 175 ppm or more calcium. No other fertilizer has values like that. I’m just afraid that calcium might block the other nutrients (phosphorus magnesium iron especially). In addition, many people use tap water, which already has some calcium in its composition. What do you think about this? Are these not dangerous values? and what is our limit, especially with tap water?
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Ya greengene is the man! I get that intro jingle stick in my head so easy…. 
I can’t answer your question about too much Ca, but I think he compares it to athena and it isn’t much higher than their blend?
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Not sure dangerous is the right word since you’re only bumping calnit for a couple weeks during the stretch. Most likely problematic though if you’re not prepared to bump other nutrients to compensate.
As SlowNickel alludes to on his IG, when you push Ca you will generally find you need to also push other nutrients like P & K. So pushing Ca that hard seems very likely to start you down the road to deficiencies in other nutrients. I think SlowNickel actually says you “uncover deficiencies you didn’t know you had” but when you consider that Ca is antagonistic against P, Mg, and others it may be in part that pushing Ca is also causing some of the deficiencies.
All that said, I’m very likely just talking out of my ass since I haven’t read nearly as many scholarly articles as others.
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Been using Jacks 321 mixed with RO 0ppm water at the recommeneded rates per the latest feed schedule on their site which I believe is:
Part A = 3.78g
Part B = 2.52g
ES = .99g
This brings my EC to 1.9 - 2.0 every single batch I have mixed up. The plants seem healthy but they have purple stems. I grow under LED and this seems to happen to every strain and every plant no matter what nutes I use. But anyway I see people feeding at a much lower rate of 1.2 - 1.4 and I am wondering if my feed strength is too high? I have one strain going right now that does not look happy and wondering if it might be too much N with the higher EC.
My main question is around mixing stock solutions because I want to setup an automated batch mixing tank using peristaltic pumps. The Jacks folks have a video out about mixing stock solutions and their advice was too do a 100x concentrated stock solution as anything higher and you can have solubility issues. So I need someone to check my math here.
so according to their feed schedule for 100 gallons you need:
Part A = 378.54g
Part B = 252.36g
ES = 98.94g
Since I want a 100x stock solution that would be all the amounts listed above but in 1 gallon of water instead of 100 gallons. But I don’t want to make 1 gallon of stock solution because I probably wont use that much before its no longer good. I would rather make 1L worth of stock solutions since most of the peristaltic pumps dose out in ML’s it will make the math easier. So there are roughly 4 Liters in a gallon (not exactly but I think close enough for my purposes). So I would divide the above listed amounts by 4 giving me the following:
Part A = 94.64g
Part B = 63.09g
ES = 24.74g
I would then add Parts A and the ES into solution A and add enough RO water till the water and the salt mix together equal 1000ml’s together. Then create solution B doing the same with Part B and enough water to make 1000ml’s. This will not actually be 1000ml’s of RO water as I want the salts plus the water to be what equals the 1000ml’s correct? If my thinking is correct then I should just be able to add in 10ml’s of solution A and 10ml’s of solution B to a gallon of water to make my final feed solution. Just need a sanity check as math is not my strong suite lol. I want to make sure I am going about this the correct way.
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After having typed all that out, I think I already see an error in my math. It wouldn’t be 10ml’s per gallon of water to get to my final feed solution I think it would be 10ml’s of each stock solution per L of water with 4L’s being in a gallon it would be roughly 40ml’s of each stock A and B concentrate to a gallon of water to get to the final feed strength. Again math not my strong suite lol so please verify if correct.
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Jacks 5-12-26(a) shows max solubility at 1lb per gal
If you wanted to make the stock solution way stronger.
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Thanks for the info brother. Max solubility according to the label is 1lb or 448grams per gallon which is pretty close to their recommendation of doing 100x concentrate which would be 378.54grams per gallon. Doing the max at 448grams makes like a 118x concentrate so not a real huge difference between it and the 100x concentrate. Plus keeping the concentration at 100x makes the math much easier, at least for me lol.
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Hi!
Please do share your adventure with perilstatic pumps, I am looking to integrate them in my Home Assistant as well!
You can get a volumetric flask and then mix the powders and top it up to an exact litre.
Also, do add like 0.1 g of Sodium benzoate/Potassium Sorbate to your stock solutions, they work as mold inhibitors and will keep your stock solution clean
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The analysis shows 5% as Ammonical Nitrogen 
Where did you see the analysis? I didn’t see it when I looked on their page.
Hi guys!
I have been using Jacks 3-2-1 and decided to leave out the epsom, I am mixing small batches of 20L and have seen my pH drift up back to 7.
I run DTW.
Any idea on how to keep the pH stable in the rez?