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CalMag usage question

ButterflyEffect

Well-known member
I know this question gets tossed around quite a bit but I'm really trying to dial things in and truly understand the media.

So, I've been using coco now for a few months. My 3 rooms are now all officially LED and coco. I should also note that I use rain water only. The calmag I use is GH Calimagic.

Should I be using the full 5ml/g as is recommended on the bottle? I read in a few places that it should be half that and now I'm wondering whether I'm short changing my plants. Based on how many 25g reservoirs and 5g buckets I mix, I would need about 5 gallons of it per year.

So should I be at 5l/g with my setup? What do y'all think?

One of the runs. GG4 cross
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Grow44DE

Well-known member
Hi @ButterflyEffect plants look great. just stick to what you are already doing.

Directions: Use 1ml per liter (1 teaspoon per gallon) for most applications. When using Reverse Osmosis or purified water add 1ml per liter (1 teaspoon per gallon) to water before adding nutrient solution. When growing in Coconut Coir or using prepared soil or soilless mixes add 1ml per liter (1 teaspoon per gallon) to wet the media and to nutrient solution for the first two weeks. Continuous use may be helpful for fast growing annuals.
 

ButterflyEffect

Well-known member
I
Hi @ButterflyEffect plants look great. just stick to what you are already doing.
I appreciate the response! These are some of the best plants I've grown in a long time for sure but I'm only at half the recommended dose currently. My top concern is using rainwater which is essentially the same as using RO, and also the fact that coco likes to bind calcium and magnesium when it can and that takes away from what's available for the plants.
 

ButterflyEffect

Well-known member
You don't need calmag. Just increase the base fertilizer you're already using. It has the same effect.
Also looks like you know what you're doing.
I'm not so convinced of that based on what I've read. Coco loves to hog up calcium and mag and I'm using the equivalent of RO water.

Thanks for the compliment! I'm coming out of a major self-caused slump and I really need to make sure I'm not missing anything. Making assumptions is partly how I got into trouble before.
 

Orange's Greenhouse

Active member
I'm not so convinced of that based on what I've read. Coco loves to hog up calcium and mag and I'm using the equivalent of RO water.

Thanks for the compliment! I'm coming out of a major self-caused slump and I really need to make sure I'm not missing anything. Making assumptions is partly how I got into trouble before.
But you're adding fertilizer to that water right? It contains all a plant needs, including calcium, magnesium and iron. Calmag contains also those three elements.
After a few good fertigations the coco is in equilibrium with the nutrient solution and doesn't have much effect anymore. It also releases/binds micronutrients. To supply those and not focus overly on calmag should be beneficial.
 

ButterflyEffect

Well-known member
But you're adding fertilizer to that water right? It contains all a plant needs, including calcium, magnesium and iron. Calmag contains also those three elements.
After a few good fertigations the coco is in equilibrium with the nutrient solution and doesn't have much effect anymore. It also releases/binds micronutrients. To supply those and not focus overly on calmag should be beneficial.
Yes I'm using Jacks A & B for my main fert regiment. Maybe I'm overthinking things but I just switched from an all perlite hempy setup that was a nightmare to keep stable so I'm a bit overzealous about this.

I know I should be using calmag every feed due to coco and pure water but I'm only at half the recommended dosage for the Calimagic now.
 

Orange's Greenhouse

Active member
Yes I'm using Jacks A & B for my main fert regiment. Maybe I'm overthinking things but I just switched from an all perlite hempy setup that was a nightmare to keep stable so I'm a bit overzealous about this.

I know I should be using calmag every feed due to coco and pure water but I'm only at half the recommended dosage for the Calimagic now.
You don't need calmag there. Just use the other nutes at the same EC as before. There are many who are successfull.
CalMag is an overpriced cannabis specific product. You don't find it in general horticulture.
 

ButterflyEffect

Well-known member
You don't need calmag there. Just use the other nutes at the same EC as before. There are many who are successfull.
CalMag is an overpriced cannabis specific product. You don't find it in general horticulture.
Thanks. I get that weed itself doesn't need it any more than any other C2 class plant. It does however need to be in RO water regardless of what type of agriculture you're in. What I suspect is there's just simply enough of Ca and Mg in many growers water that it just isn't a concern. That or if they do use RO or rainwater, they use a nutrient formula that's already compensated for it.

That said, if I drop the calmag, my plants would suffer greatly no matter the media I use. Been using rain for ten years now and I've tested that theory much to my peril. I'm now trying to factor the effect of coco into this equation
 

Rocket Soul

Well-known member
D
One thing you can do in order to avoid the whole calmag problem with coco is to feed at approx 50% extra nute strength at transplant in order to buffer the coco, but this depends if the coco is properly buffered already. Worked for us, ymmv :)
 

DaEarl73

Well-known member
Thanks. I get that weed itself doesn't need it any more than any other C2 class plant. It does however need to be in RO water regardless of what type of agriculture you're in. What I suspect is there's just simply enough of Ca and Mg in many growers water that it just isn't a concern. That or if they do use RO or rainwater, they use a nutrient formula that's already compensated for it.

That said, if I drop the calmag, my plants would suffer greatly no matter the media I use. Been using rain for ten years now and I've tested that theory much to my peril. I'm now trying to factor the effect of coco into this equation
How high is your ec of the rainwater? I would add calmag until getting 0.8ec and would add the other nutrientes like before until reaching the Desired ec. Worked for me on coco, just my 2cents
 

Rocket Soul

Well-known member
D
If the Environment is dialed in you can feed them like beasts, always until runoff. Like someone mentioned some feed their plants multiple times a day to get them to go fullon mode
Imo opinion you should always look for run off, its the only way to control how much nutes you have in the coco, always check ec out. If you have a pot full of roots you can multifeed but weve never done it our grow, too big pots.
 

ButterflyEffect

Well-known member
Imo opinion you should always look for run off, its the only way to control how much nutes you have in the coco, always check ec out. If you have a pot full of roots you can multifeed but weve never done it our grow, too big pots.
Hey. Thanks for checking in! I do monitor runoff as I do high frequency fertigation. It only runs to runoff once a day due to not having enough rain lately but I typically do. They get 5 feeds per day after stretch.

With the Jacks, I use Recharge and a bit of extra kelp and fulvic. Max feed is 1.6-1.7 EC
 

ButterflyEffect

Well-known member
If the Environment is dialed in you can feed them like beasts, always until runoff. Like someone mentioned some feed their plants multiple times a day to get them to go fullon mode
Thanks for chiming in! Much appreciated

Rainwater is around 20ppm. I just tested and at the rate I've been using the Calimagic, it adds about 185ppm of calmag. Somewhere in the 0.4 EC area.

My environment is fully automated. Temp @ 78F and humidity @ 60-65. Canopy is near identical, so the VPD is ~1.3.
 

Rocket Soul

Well-known member
D
These are the DIY rings I use. The manifold is on the right
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These are the reservoirs and pumps. The feed 5 pulses per day, to runoff every time if I have the water supply, at least once if I don't
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The lady of photo 3 is a real bondage queen, you sure bent her over, lol.
Nice pics, i wish i could get jacks in euro. Does anybody know a way?
 
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