Jacks 321 with RO water help and question!

[Jack123321]

Do you need to add calmag(bottle) when using Jacks 321 to buffer the RO water or can you just increase part b(cal) and Epsom(mag)? I also noticed some PH issue with straight RO so im cutting it with Tap and got around 80ppm and I dont need to PH my water with Jacks 3.6/2.4/1.2. Ive been having magnesium deficiency with jacks321. Im also doing Drain to waste with coco coir/perlite 70/30 mix.

 

[Dr.Dutch]

CalMag is usually calcium nitrate and magnesium sulfate. So you can also just take the one from Jack and the Epsom.

 

[Jack123321]

CalMag is usually calcium nitrate and magnesium sulfate. So you can also just take the one from Jack and the Epsom.

Thanks for the reply, that was my plan. Was going to increase the epsom salt first to 1.5/g and see if the extra Magnesium helps since im in Coco with RO water and also LED. Ive been running into high light intensity and I think its also causing the Magnesium issue. So I can just use 50/50 RO and tap to stabilize my PH and then add Part A -> Epsom -> part B without needing to add Calmag in the beginning?

 

[ArtfulCodger]

I run Jack's in coco. The first thing I ask when I see a mag deficiency in coco is whether the coco was well-buffered to begin with. Unbuffered coco will gobble up a lot of Mg. The next question is light intensity. If you're seeing taco-ing or curl on your tops, it might be an indication that you're giving more light than the plants want at that stage. Of course, unbuffered coco plus too much light is a fairly dependable way to create a mag deficiency. If your coco was buffered and your light intensity is good, then bump the epsom salt.

 

[Jack123321]

I run Jack's in coco. The first thing I ask when I see a mag deficiency in coco is whether the coco was well-buffered to begin with. Unbuffered coco will gobble up a lot of Mg. The next question is light intensity. If you're seeing taco-ing or curl on your tops, it might be an indication that you're giving more light than the plants want at that stage. Of course, unbuffered coco plus too much light is a fairly dependable way to create a mag deficiency. If your coco was buffered and your light intensity is good, then bump the epsom salt.

What kind of lights are you using? If you’re running LEDs, do you just run jacks 321 at those ratios? Also are you using tap water? I’m also using canna coco bags and they come prebuffered. I have been trying to get my ppfd to around 400-500 during veg(week 8) but I noticed light stress and also magnesium deficiencies when I push them that high. I dimmed the lights down to 300-350 ppfd and I feel like they should be able to handle higher PPFD at those stages. I’m also at 18/6 light cycle so DLI is not crazy high either. Am I lacking elsewhere, I feel like I should be able to push my lights a little stronger. Hence why I’m thinking it has to do with this magnesium deficiency due to strong LED requiring more Calmag and I don’t have enough at those high ppfd? As you can tell I’m pretty new so I have a lot of questions and things I’m unsure of.

 

[Peat_Phreak]

3.6/2.4/1.2 is not a great formula for weed. It has too much K which competes with Ca and Mg. It also doesn't have enough Ca. Adding more Mg is not going to help here.

Which Jacks formula to use for weed depends on the media, how often you feed, the EC and the light source.

And if you have a cal mag issue, the fastest way to fix it is with a CalMag foliar treatment or two.

 

[Jack123321]

3.6/2.4/1.2 is not a great formula for weed. It has too much K which competes with Ca and Mg. It also doesn't have enough Ca. Adding more Mg is not going to help here.

Which Jacks formula to use for weed depends on the media, how often you feed, the EC and the light source.

And if you have a cal mag issue, the fastest way to fix it is with a CalMag foliar treatment or two.

Thanks for the information. Ive been watching Greenegenes video and ive attached the nutrient break down of jacks321 and at full strength youre getting around 205(K). even Athena line which alot of people have success with is at 263(K). I also noticed Greenegene and some people switch to the 4/2 formula and that has even more K and less Calcium. Any input would be greatly appreciated. Ive also tried CalMag foliar treatment but it didnt fix the issue :( did it a few times throughout the weeks during lights off.

In terms of formula, Ive been trying to stick to Jacks321 and tweaking it slowly once I get a few more grows under my belt. If you have any recommendations on a better ratio with my media and light source that would be great!

Here are my specs and how im running my recent grows:

LED light: HLG 350R
Media: Coco coir + perlite 70/30
Water: 50/50 Tap/RO (using tap to buffer the PH and at full strength I dont need to PH my water at all but I do check every time)
Water style: High frequency fertigation 1/day early veg to 3/day late into flower (always around 10-15% runoff)
EC: 2.0
Nutrients: Jacks 3.6/2.4/1.2
PPFD: early veg 200, veg 300-400, flower 600-700 (tried upping ppfd but always get plant stress and mag deficiencies)
Temp: 78 (leaf temp around 75)
humidity: Veg 65-70, flower 60-50

 

[ArtfulCodger]

What kind of lights are you using? If you’re running LEDs, do you just run jacks 321 at those ratios? Also are you using tap water? I’m also using canna coco bags and they come prebuffered. I have been trying to get my ppfd to around 400-500 during veg(week 8) but I noticed light stress and also magnesium deficiencies when I push them that high. I dimmed the lights down to 300-350 ppfd and I feel like they should be able to handle higher PPFD at those stages. I’m also at 18/6 light cycle so DLI is not crazy high either. Am I lacking elsewhere, I feel like I should be able to push my lights a little stronger. Hence why I’m thinking it has to do with this magnesium deficiency due to strong LED requiring more Calmag and I don’t have enough at those high ppfd? As you can tell I’m pretty new so I have a lot of questions and things I’m unsure of.

I veg under 6500K T5s and flower under LEDs. I run Jack's 321 at 1.3 EC in veg and 1.8 EC in flower. I use RO water to make my stock solutions, but mix my feed with 80 ppm tap. In recent runs, I've tried 421 for the first five weeks of flower, but I'm not sure it makes a big difference. Results with 321 were great, results with 421 are also great. I'm in 100% Canna coco (bags) with Blumats.

This is probably a minority opinion, but I let the plants dictate the light levels. Praying an hour before lights out = more light please. Flat and level = happy. Taco-ing, curling, twisting, canoe-ing, tips & stripes = too much light. Light, water, nutes, and environment work in balance...we can't just push one and expect the plants to dig it.

 

[Jack123321]

I veg under 6500K T5s and flower under LEDs. I run Jack's 321 at 1.3 EC in veg and 1.8 EC in flower. I use RO water to make my stock solutions, but mix my feed with 80 ppm tap. In recent runs, I've tried 421 for the first five weeks of flower, but I'm not sure it makes a big difference. Results with 321 were great, results with 421 are also great. I'm in 100% Canna coco (bags) with Blumats.

This is probably a minority opinion, but I let the plants dictate the light levels. Praying an hour before lights out = more light please. Flat and level = happy. Taco-ing, curling, twisting, canoe-ing, tips & stripes = too much light. Light, water, nutes, and environment work in balance...we can't just push one and expect the plants to dig it.

Thanks for that write up, its super helpful. I was thinking of trying 421 in one of my future grows after I get 321 down. During flower with jacks, did you ever had to tweak part B or epsom? I know genetics play a part too but I want to get better at dialing in the part B(cal-nit) and Epsom(Mag-Sul) with deficiencies for Mag as thats what im seeing. Also totally agree with the balance aspect as I assume that's how y'all are growing some amazing plants with your dialed in environment. Im on my journey with dialing my environment but I keep getting stuck on this LED intensity and nutrient deficiencies. I feel like I have everything down except the proper light to nutrient ratio in coco(hydro). I just cant seem to push my lights to what people online are recommending for PPFD and I havnt been able to use my lights at more than half strength during flower. Im also in a 3x9 grow space with 2 HLG 350R, so about 3x3 space for each 350R. Ive also tried the recommended 24inch height during veg and 15inch during flower with the lights dimmed. At one point I suspect my ambient CO2 level and not enough air exchange but I do have the AC infinity inline fans and 2 oscillating fans so I dont really think its CO2 as thats probably the last thing it can be.

 

[Dr.Dutch]

I don't like any of the formulations. There is clearly too much P in all of them(1). If you want to follow the latest research: I finished the data today.
In the yellow on the left the USU Solution(2) calculated to 85% and on the right the values from the NCSU article(3) calculated according to the table from the USU on the right(4).
PS: Iron is also way too high in all formulas on your table

And a small correction to earlier post: CalMag usually consists of calcium and magnesium nitrate. Sulfate should not be contained in it, that should also lead to problems in connection with calcium. (Was still early in the morning, sorry )

 

[Jack123321]

I don't like any of the formulations. There is clearly too much P in all of them(1). If you want to follow the latest research: I finished the data today.
In the yellow on the left the USU Solution(2) calculated to 85% and on the right the values from the NCSU article(3) calculated according to the table from the USU on the right(4).
PS: Iron is also way too high in all formulas on your table

View attachment 1959986

And a small correction to earlier post: CalMag usually consists of calcium and magnesium nitrate. Sulfate should not be contained in it, that should also lead to problems in connection with calcium. (Was still early in the morning, sorry

It looks like I have alot of research to do since I dont know what the ratio or optimal PPM of each elements. From your screenshot I see that Mg at 100% for USU is 19ppm. Isnt that consider low for cannabis as I see people saying optimal is 50-75PPM or am I reading this chart wrong? And yeah I see that Iron for jacks321 is at 2.8, but I see 0.4 for usu. It doesnt seem like theres much I can tweak with Jacks as most of the trace minerals are in Part A, I feel like I can lower the feeding to hit some of the lower numbers but then I will also lower NPK . Also Part B is only Calcium nitrate. I also just recently bought the 25 pound bags so Im committed to jacks lol.

 

[Peat_Phreak]

Water style: High frequency fertigation 1/day early veg to 3/day late into flower (always around 10-15% runoff)
EC: 2.0

I can't help you with nutes for that set up. But I can tell you what works for me with one big feeding 15x a month.

1.25 part A to 1.00 part B is the basic ratio. Use whatever ppm is appropriate for each stage.

zero epsom salt

I max out at 5g of part A and 4g of B. But more can be used. I don't get leaf problems.

 

[ArtfulCodger]

...I feel like I have everything down except the proper light to nutrient ratio in coco(hydro). I just cant seem to push my lights to what people online are recommending for PPFD and I havnt been able to use my lights at more than half strength during flower...

You have 39 watts of LED per square foot (that's a lot). Maybe it's possible to finish healthy plants at 1,000 ppfd indoors without supplementing CO2, but I've never done it. I haven't had to mess with the epsom ratio. When I see light stress, I turn down my lights. I can't smoke photons.

 

[Dr.Dutch]

It looks like I have alot of research to do since I dont know what the ratio or optimal PPM of each elements. From your screenshot I see that Mg at 100% for USU is 19ppm. Isnt that consider low for cannabis as I see people saying optimal is 50-75PPM or am I reading this chart wrong? And yeah I see that Iron for jacks321 is at 2.8, but I see 0.4 for usu. It doesnt seem like theres much I can tweak with Jacks as most of the trace minerals are in Part A, I feel like I can lower the feeding to hit some of the lower numbers but then I will also lower NPK . Also Part B is only Calcium nitrate. I also just recently bought the 25 pound bags so Im committed to jacks lol.

Ok, then you have something for the future with the links. You definitely get it right, the data strongly suggests that magnesium is also given too much.
It surprised me at first too, even though I consider the Utah State University and Dr. Bugbee to be very reliable sources. But they are all confirmed by the North Carolina State University analysis.

Jacks is a "normal" fertilizer, right? I work with similar here, Compo Expert Hakaphos. These also all contain too much iron and too little boron (but so do all fertilizers that are "specifically" for canna...).
With 25 you get along anyway a lifetime, there you could also now think about other products. I would not wait until it is empty.

 

[Peat_Phreak]

Jacks is a "normal" fertilizer, right? I work with similar here, Compo Expert Hakaphos. These also all contain too much iron and too little boron (but so do all fertilizers that are "specifically" for canna...).

Jacks321 isn't made exclusively for cannabis. It's widely used in horticulture and agriculture.

I've used it for a couple years. Iron or Boron issues have not been a problem. Leaf issues in general have not been a problem.

Jacks is popular because it's cheap and good quality. No heavy metals.

 

[ArtfulCodger]

One of the things I appreciate about Jack's/Peters is that because hobby cannabis isn't their main business, they've been testing their stuff thoroughly for years so their main customers, large farms, know what they're buying. I'm slightly amazed when I see cannabis nute labels that show ingredients that aren't listed in the guaranteed analysis.