More Calcium and Nitrogen with Jacks or Masterblend???

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I have consistently run into Calcium issues and my plants are never that Dark Green.
I know strains vary in their degree of Greenness.

I also know there are other reasons like temperature humidity and air movement and Other Macro Nutrient Rations that can effect calcium Uptake.

That said please entertain me.

I have read some people using a Jacks 2-2 or 2-2-1 and Loving it. Not sure how many top ups in RDWC I could do before the Nitrogen or Calcium might build up TOO HIGH?
Ironically I just got some Masterblend and it premixes much better but the irony is I got it because I liked the 2-2-1 Formula not that my 250/165/64 (Liter of Water) 1000ml) was anything but a Math calculation...

I think the Masterblend Premixes better because of the lack of Magnesium Sulphate maybe???

Anyway I could make my Master Blend more like a 3-4-1.5 or 2-2.5/1 to achieve this and some Say Masterblend is a little low in N?

Anyone here run Jacks in Veg closer to 3-3-1 or 2-2-1 or whatever. I think my plants need more Calcium.

MY Leaf Surface Temperatures are a little low sometimes 75 ish instead of 80 and cooler at night and in the morning but I am adding back CMH to my LEDS here in VErmont in Winter to see how much my LST is causing Calcium absorbtion issues.

Also sometimes I get lazy and top off my Reservoirs for a week or more instead of changing it out.

Also I am starting to think my 1 tsp per gallon of Potassium Silicate might be throwing off my Numbers K ----- Ca ratio.

I am switching to Mono Silicic Acid.

My PH tends to run a little high in VEG like 6.5-7 but I thought Calcium best absorbs in that range.

I have seen a Chart that suggests otherwise lower PH for Calcium in Hydro...

Any other ideas...

Thanks for your time...


Both call for 2.4 grams of Calcium Nitrate so the calcium level will be the same.
Jacks has a higher MG level
I ran Jacks for years but had to run Masterblend this time. I’m more than pleased. It mixes better than Jacks and up to now, week 2 of flower, it’s performing well, @ 2.5 2.5 1.25. If anything, they could’ve used more N but there wasn’t a deficiency of anything, visible.
You can add CA without raising the N by using Calcium Sulfate. @Greengenes Garden is running Jacks at 4 and CS at 2.
Here’s info on supplementing with CS.

At 20C (68F), calcium sulfate dihydrate – the form most commonly available – has a solubility of around 2.4 g/L. In practice this means that you can have up to around 550 ppm of Ca in solution from calcium sulfate dihydrate before you observe any precipitation happening. This is way more than the normal 150-250 ppm of Ca that are used in final hydroponic nutrient solutions that are fed to plants.


Just wanted to say if you're going the scientific route. You will never truly know unless you have your soil or water tested and understand it's intricacies. My understanding of my girls is strictly soil, dirt, compost etc. I would love to be able to dable into hydro. I'm just not at that level or complete understanding. What ever you choose to try and understand. Always be gentle and light hand with your approach. Watch them crawl before you put them in the races. Because once you do, you have very little time to correct the issues involved. Much respect. One love


I'm in rdwc. 90 gallons
Per gallon
1/2 tsp of potassium silica
1 ml calmag plus iron
1.9g Jack's part A
1.25g Jack's part B

This seems to be a sweet spot for me. I also haven't swapped out the res, just top offs with 50% nutes.

My ppm starts at 600ppm and then after 2 weeks it drops to about 425 with a slight PH increase to 6.2.

I'm not sure about salt buildup or anything. I haven't seen any issues after a month. Im also running full beneficial bacteria and myco's with Mr fulvic.


This is what I use for veg at peak demand

jacks 5/12/26 - 4g per gallon
calcium nitrate - 4g per gallon
epsom salt - zero

fed 15X a month in peat

Any minor leaf issues that may occur can be sorted out with some Cal Mag foliar treatments.


I love masterblend much better than jacks, specifically because it has no mag sulfate. 25lbs is cheaper too than jacks if you factor in zero mag sulfate weight in the jacks bag. Its such a pretty blue as well. lol

I tweak masterblend throughout the plants life. Ill use magnesium nitrate in veg, in addition to mag sulfate to bump up the nitrogen. calcium sulfate the entire time as well. Im in coco, and need the extra calcium and magnesium. One time i tried to replace all the mag sulfate, with mag nitrate and got sulfer deficiency. I feel calcium sulfate is needed with masterblend, it has zero sulfer to begin with. Ill add mono potassium phosphate to bump the phosphorus the first couple weeks of flower as well. I have some potassium sulfate on my to do list, to work that into the equation at some point. But running Masterblend at 3-3.5 grams a gallon late flower bumps potassium nicely, without the need for more micros. Masterblend is heavy on micros as it is, other than iron.

I started my raw salt journey with jacks a couple years ago. BEFORE i learned about masterblend. ill never buy jacks again actually.

Yall better save me some, im almost out. lol. 80 bucks to your door for 25lbs, is what jacks USED to be...

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