Jacks 321 grams per gallon wtf?!! Why am i out of the loop.

I keep getting different answers on jacks 321, running in strait coir under led, jacks 321 recipe uses 3.79 grams part a, 2.52 grams part b and .99 grams epsom salt. I keep reading post of people using 3 grams part a 2 grams part b and 1 grams epsom. What grams per gallon am I actually supposed to be using. Also does anyone supplement calmag when using ro water half the people on one forum says no cal mag and on another forum they say to use calmag. I'm so confused. And what is up with the 1 to .67 ratio I keep reading about. I ran jacks last grow and ran into odd issues and started another grow and the same issues popped up odd rust colored leaves that get progressively worse. I'm 2 weeks in on this grow and running 400ppm jacks on the .5 scale slowly walking up the ppm every few days.

The Calcinit and Epsom are your calmag. There is no need for more.
Some are anal about their measurements. I just go by volume and dilute to desired EC.
I stick to the 3-2-1 ratio. Also in straight coco under LED. Not RO but close as my tap water is about 30ppm.
These plants are getting 1.0EC/500ppm 2x/day.

So your going by volume, so 3 scoops part a 2 scoops part b and 1 scoop epsom salt. Could applying to much cal mag cause potassium deficiencies?? Applying too much calcium and magnesium can cause a. potassium deficiency;( the K/Ca and K/Mg ratio should always be kept above 2 (but below 10, since too much K can hinder the absorption of calcium and magnesium). Too much potassium can also prevent the absorption of certain micro-elements, such as zinc. It is particularly important to take account of this interaction when using very hard water with a high calcium and magnesium content.) Per canna nutrients website

Hiddengardener said:

So your going by volume, so 3 scoops part a 2 scoops part b and 1 scoop epsom salt.

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Yes

Hiddengardener said:

Could applying to much cal mag cause potassium deficiencies??

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Yep. We see it here all the time.

Hiddengardener said:

Per canna nutrients website

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Did you know? They didn't sell a calmag product until fairly recently. I don't know if they changed their nute line to make it necessary but. you didn't need it before.

Ok thank you tons, I feel like I'm chasing my tail sometimes

3.6/2.4/1.2 is the full strength ratio

So let's say I follow the ratios and still get a calcium or magnesium deficiency would I increase the ppm of my mixture more nutes less water of would I try and change the ratios around ??

Hiddengardener said:

So your going by volume, so 3 scoops part a 2 scoops part b and 1 scoop epsom salt. Could applying to much cal mag cause potassium deficiencies?? Applying too much calcium and magnesium can cause a. potassium deficiency;( the K/Ca and K/Mg ratio should always be kept above 2 (but below 10, since too much K can hinder the absorption of calcium and magnesium). Too much potassium can also prevent the absorption of certain micro-elements, such as zinc. It is particularly important to take account of this interaction when using very hard water with a high calcium and magnesium content.) Per canna nutrients website

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Yes the ratio is by volume but you need to measure your EC before feeding. Yes excess calcium, magnesium, or nitrogen can lockout potassium.

Thank you all.

The feed sheet (click the link to download the PDF) calls for the ratio of 3.79-2.52- 0.99. I've seen a lot of references to 3.6 and 2.4 and that's the same ratio as 3.79 and 2.52. What's different is the Epsom salts ratio. Personally, I don't add the Epsom salts because there's enough Mg and S in A and B for my liking.

Delps8 said:

The feed sheet (click the link to download the PDF) calls for the ratio of 3.79-2.52- 0.99. I've seen a lot of references to 3.6 and 2.4 and that's the same ratio as 3.79 and 2.52. What's different is the Epsom salts ratio. Personally, I don't add the Epsom salts because there's enough Mg and S in A and B for my liking.

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Are you growing in coir?

Jacks has recently changed their recommended ratios, hence much of the confusion. They currently call for less MagSul than they did in the past.

Hiddengardener said:

Are you growing in coir?

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DWC.

Gemtree said:

3.6/2.4/1.2 is the full strength ratio

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It used to be, but for some reason Jacks is now recommending 3.79-2.52-0.99. Not sure if they’ve altered the formulation or what.

PJ Diaz said:

Jacks has recently changed their recommended ratios, hence much of the confusion. They currently call for less MagSul than they did in the past.

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The 3.6/2.4/1.2 formulation is a 3-2-1 ratio when the divisor is 1.2

The new ratio of 3.79-2.52-0.99 is 3-2-0.78 when the divisor is 1.26 which is a 27% drop. They also show 3.7-2.5-1.1.

And it will be “Human sacrifice! Dogs and cats living together! Mass hysteria!” when they change it to 76-50-20…

Delps8 said:

The 3.6/2.4/1.2 formulation is a 3-2-1 ratio when the divisor is 1.2

The new ratio of 3.79-2.52-0.99 is 3-2-0.78 when the divisor is 1.26 which is a 27% drop. They also show 3.7-2.5-1.1.

And it will be “Human sacrifice! Dogs and cats living together! Mass hysteria!” when they change it to 76-50-20…

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Soon, they will likely suggest that folks cut their CalNit with CalChlor to reduce N during flowering like Josh does.