First timer here - Seedling Nutrient Dilution

Hi All -

My first grow is within its first week!

I'm following the Coco For Cannabis recommendations - 70/30 coco mixture from bricks and General Hydroponics nutrients

Coco has been buffered twice with 7.5mL Calmag/gal water.

I have 1 seedling going (Twenty20 HOT DAMN autoflower) and I am preparing to transplant into a solo cup.

When following the Coco for Cannabis seedling feed chart, I've mixed a gallon of full strength nute soltuion - CalMag 5ml, Micro 1.25ml, Gro 0.6ml, Bloom 0.6ml, Diamond nectar 2.5ml to a gallon of water.
My EC of this solution is around 900.

Now to my understanding I need to dilute this with a calmag water to keep the calmag levels the same in my final product. So in addition to mixing my nutes, I have mixed a separate gallon of water with 5ml calmag.

Next I took a small sample of my nute solution, which has an EC of 900, and began to dilute it with my CalMag/Water. It seems I have to REALLY dilute this solution to achieve a 400EC... so much that im questioning if this is the correct way.

My questions -
1 - Should I be diluting with plain water or calmag/water?

2- If I have to dilute the solution so much, should I be starting with a fraction of the nutes to arrive closer to my target EC of 400?

3 - How do you all prepare for feeding your seedlings?

Thank you for reading this and any help you may have to offer!

You must mean PPM not EC. 300 ppm is what I usually start seedlings at them work up from there. 300 ppm is 0.6 EC on the Hanna scale.

Just add some CalMag to the nutes and water with that. No need to have them separate. Micro first, then the others and CalMag at the end is fine.

lunchbox22 said:

If I have to dilute the solution so much, should I be starting with a fraction of the nutes to arrive closer to my target EC of 400?

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I use AN 3 part and 1ml/L of each ends up around 300ppm. 440 ppm should be fine and don't keep the leftovers more than a few days unless aerating as they go bad fast. Cool, dark place and they'll keep longer but best used fresh.

OldMedUser said:

You must mean PPM not EC. 300 ppm is what I usually start seedlings at them work up from there. 300 ppm is 0.6 EC on the Hanna scale.

Just add some CalMag to the nutes and water with that. No need to have them separate. Micro first, then the others and CalMag at the end is fine.



I use AN 3 part and 1ml/L of each ends up around 300ppm. 440 ppm should be fine and don't keep the leftovers more than a few days unless aerating as they go bad fast. Cool, dark place and they'll keep longer but best used fresh.

Click to expand...

Thanks for the information! My original mixture of nutrients has a full does of Calmag in it. I was under the impression that when I dilute this to the proper strength I should not be diluting with plain water and instead I should be diluting with a calmag water to keep the levels up to help avoid a calmag deficiency.

I’m a long time gardener but have always grown in soil. This is my first cannabis attempt and I’m working with coco so I may just be overthinking every step.

As far as my meter I believe it measures in microsiemens per cm which explains the higher number I listed. (I’m also new to this type of data so still I’m learning all the terminology)

I appreciate you taking time to respond! Happy growing

lunchbox22 said:

Thanks for the information! My original mixture of nutrients has a full does of Calmag in it. I was under the impression that when I dilute this to the proper strength I should not be diluting with plain water and instead I should be diluting with a calmag water to keep the levels up to help avoid a calmag deficiency.

I’m a long time gardener but have always grown in soil. This is my first cannabis attempt and I’m working with coco so I may just be overthinking every step.

As far as my meter I believe it measures in microsiemens per cm which explains the higher number I listed. (I’m also new to this type of data so still I’m learning all the terminology)

I appreciate you taking time to respond! Happy growing

Click to expand...

I've used hydro nutes for 4 years and when using 3-part nutes you are supposed to put in the Micro first then the others in any order. Then I would add the CalMag tho I never used it for the first 30 years and think people use too much too often which can screw things up. If using silica in hydro that should be fed on it's own after dilution and pH adjustment as it can raise the pH up to 10. Makes good pH Up if that is needed tho not often unless you overshoot with the pH Down.

I'm going to be getting back into it in the fall to produce lots of meds but still be growing in pots for my breeding and fem seed projects.

Silica> calmag > micro > whatever else