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CalMag usage question

Grapefruitroop

Active member
Yeah man IME, Leds plus coco means you cant never overfeed magnesium and calcium.....:pie:
You can get10lb bags for very cheap on amazon of Calcium Nitrate and Magnesium Sulphate.

I use Masterblend as base formula
 

stiff

Well-known member
Veteran
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.
You DO need calmag if you grow in coco! Specially under LED lights.

You might have missed the part where he said he's on coco...or you're just wrong.
I grow outdoors in coco and give it less of it compared to whats in my tents,but you definitely need to provide some sort of calcium and magnesium.

How much you add is up to your lights and your tab water. The guideline on the bottle is a rough estimate and usually on the higher side,as the company wants to sell their products.

I have to agree with @Grow44DE
Your plants look fine, I'd also be continuing this way.
Besides that..Here's a little guide which helped me a lot when i was nrw to it, but be aware that I use 400w LED and also a 650w. You need less if your light isn't as powerful!

A seedling wants about 50mg of calcium per liter of water you give it.

A plant in veg about 40cm tall probably about 100mg/L

A plant in full flower probably around 150mg/L ..even more if it's a hungry plant.

Now also don't forget that your water might already have calcium and magnesium in it, you teally have to get it tested if you want to use the calmag precisely...or read the water analysis results usually on the homepage of your provider availablefor free,that's if its tab water.

As an example if your tab water has 80mg of calcium and 20mg magnesium and you goal is to give it 150mg cal and 50mg magnesium..then all you have to do is add that much that it gets you to those numbers.
It's just a calculation!
(Calcium to magnesium ratio should always be 3:1)
I hope it helps anyone new to coco and calmag
 

Orange's Greenhouse

Active member
You DO need calmag if you grow in coco! Specially under LED lights.
My plants tell a different story.

Say, what is special about calcium in a calmag bottle that calcium in calcium nitrate lacks? Is it energetically superior by overspending on it? Has it the correct information infused by reading the label on the bottle?
 

Chuckeye

Well-known member
You DO need calmag if you grow in coco! Specially under LED lights.

You might have missed the part where he said he's on coco...or you're just wrong.
I'm also seeing different results, I've Never added Cal/Mag !

I've grown with city water, store bought spring water and currently my well water and I feed with Mega Crop one part which has Cal/Mag incorporated in their formula.

Bottom right plant is in coco (5 days younger) and the other three are in ProMix HP. Phlizon 640w LED.

Water ppm's ~500, ph 7.5, current feed is 3.6g/gallon of MC, No extra Cal/Mag, No ph down !

Day 10 of 51 The Girls high 6 Nov.jpg


I just get the feeling adding Cal/Mag is suggested too often as The Fix. When more information is offered on the grow it usually turns out to be some other issue.

Cheers
 

Grapefruitroop

Active member
I think we need to streighten up things here....Its getting confusing....:geek:

The plants of the OP looks good and prolly no need of extra cal mag....

Its also true like Orange Greenhouse was sayn, that bottled calmag its just a cannabis green tax thing and it is waaaay overpriced at the point that can be considered rippoff....

But its also undeniable that plants between coco, LED lights and Co2 they do need an extra bump in N Ca and Mg COMPARED to the ones growing under HPS or natural sunlight...

Nutrients in powder form like calcium nitrate, magnesium sulphate etc are dirt cheap
For the same price of a 1 Liter Calcium Acetate from Canna nutrients i got 35 liters tank of the same exact nutrient, same exact concentration that is still sitting in the garage....
Peace to everyone and happy growing!!:tree:
 

ButterflyEffect

Well-known member
Yeah man IME, Leds plus coco means you cant never overfeed magnesium and calcium.....:pie:
You can get10lb bags for very cheap on amazon of Calcium Nitrate and Magnesium Sulphate.

I use Masterblend as base formula
Agreed. You're telling me that I can reliably make my own Calmag? That's something I need to look into
 

ButterflyEffect

Well-known member
You DO need calmag if you grow in coco! Specially under LED lights.

You might have missed the part where he said he's on coco...or you're just wrong.
I grow outdoors in coco and give it less of it compared to whats in my tents,but you definitely need to provide some sort of calcium and magnesium.

How much you add is up to your lights and your tab water. The guideline on the bottle is a rough estimate and usually on the higher side,as the company wants to sell their products.

I have to agree with @Grow44DE
Your plants look fine, I'd also be continuing this way.
Besides that..Here's a little guide which helped me a lot when i was nrw to it, but be aware that I use 400w LED and also a 650w. You need less if your light isn't as powerful!

A seedling wants about 50mg of calcium per liter of water you give it.

A plant in veg about 40cm tall probably about 100mg/L

A plant in full flower probably around 150mg/L ..even more if it's a hungry plant.

Now also don't forget that your water might already have calcium and magnesium in it, you teally have to get it tested if you want to use the calmag precisely...or read the water analysis results usually on the homepage of your provider availablefor free,that's if its tab water.

As an example if your tab water has 80mg of calcium and 20mg magnesium and you goal is to give it 150mg cal and 50mg magnesium..then all you have to do is add that much that it gets you to those numbers.
It's just a calculation!
(Calcium to magnesium ratio should always be 3:1)
I hope it helps anyone new to coco and calmag
Thanks. This is very helpful and informative.

The other reason I know I need Calmag is that I use rainwater with a TDS of 20ppm, so basically like RO water. For me, this post is about tying up loose ends in my grow and ensuring I don't miss anything.
 

ButterflyEffect

Well-known member
I think we need to streighten up things here....Its getting confusing....:geek:

The plants of the OP looks good and prolly no need of extra cal mag....

Its also true like Orange Greenhouse was sayn, that bottled calmag its just a cannabis green tax thing and it is waaaay overpriced at the point that can be considered rippoff....

But its also undeniable that plants between coco, LED lights and Co2 they do need an extra bump in N Ca and Mg COMPARED to the ones growing under HPS or natural sunlight...

Nutrients in powder form like calcium nitrate, magnesium sulphate etc are dirt cheap
For the same price of a 1 Liter Calcium Acetate from Canna nutrients i got 35 liters tank of the same exact nutrient, same exact concentration that is still sitting in the garage....
Peace to everyone and happy growing!!:tree:
Excellent points here.

Let's also keep in mind that my water source(rain) needs to be treated like RO so Calmag is a must for that alone.

That said, I'm interested in making my own from dry supplements if it can be done reliably
 

Grapefruitroop

Active member
I found this few years ago but dont remember where....damn....

“Common hydroponic fertilizers recipes, usually contain between 40-60ppm Mg. We have found that a range or 75-90ppm of Mg to ideal under LED lighting. The best way to increase only Mg and not introduce more nitrogen, is to add 1gram of epsom salt(Magnesium Sulfate) per gallon of nutrient solution. 1gram/gallon of epsom salt adds ~25ppm of Mg and 30ppm of S, and is usually a sufficient supplement to most fertilizer programs.”

At the time i was looking to add just magnesium because i tought that at the end of the flowering extra N could hurt, but i was wrong cause under those conditions i needed also much more N and Ca of course..
 

Orange's Greenhouse

Active member
Agreed. You're telling me that I can reliably make my own Calmag? That's something I need to look into


Here is a recipe to make your own. It's pennies on the dollar because you're not buying and shipping water.

But you don't need to treat your water prior to adding fertilizer. You just add the fertilizer. That stuff contains all a plant needs (that's kinda the definition).
 

stiff

Well-known member
Veteran
I think I got misunderstood. I use calmag..and I also use calnit and epsom salts too.
Either one of it will do the trick.
I agree that calnit and epsom salt is way cheaper than calmag.

But the ones that grow without using any of it,will probably have enough in the water so the plants haven't got a deficiency.
If you look careful at the first pics you can see little spots which look like calcium deficiency, but nothing to worry about..it's minor.
If my plants look like the ones from @Chuckeye I wouldnt change anything either, they look stunning.

My point was that, to really know what's going on, you need to know what's in your water and go from there
 

stiff

Well-known member
Veteran
Thanks. This is very helpful and informative.

The other reason I know I need Calmag is that I use rainwater with a TDS of 20ppm, so basically like RO water. For me, this post is about tying up loose ends in my grow and ensuring I don't miss anything.
I got a similar scenario..in oz we use mostly damwater which comes with almost the same nutrients in it as yours.
So bad, that Canna made a special calmag line for Oz. It's more concentrated than the European version.

Again...if the plan was to find a cheap substitute, calnit and epsom will do you just fine
 

ButterflyEffect

Well-known member
I found this few years ago but dont remember where....damn....

“Common hydroponic fertilizers recipes, usually contain between 40-60ppm Mg. We have found that a range or 75-90ppm of Mg to ideal under LED lighting. The best way to increase only Mg and not introduce more nitrogen, is to add 1gram of epsom salt(Magnesium Sulfate) per gallon of nutrient solution. 1gram/gallon of epsom salt adds ~25ppm of Mg and 30ppm of S, and is usually a sufficient supplement to most fertilizer programs.”

At the time i was looking to add just magnesium because i tought that at the end of the flowering extra N could hurt, but i was wrong cause under those conditions i needed also much more N and Ca of course..
I don't know what the ppms of my Jack's 5-12-26 has but I do know that it's listed on the label as 6.3%. It's been long held that Jack's had more than enough mag but is that the case here? Dunno but I'd sure like to know what that percentage equals in terms of ppms
 

ButterflyEffect

Well-known member


Here is a recipe to make your own. It's pennies on the dollar because you're not buying and shipping water.

But you don't need to treat your water prior to adding fertilizer. You just add the fertilizer. That stuff contains all a plant needs (that's kinda the definition).

Thanks I'll check that out. I agree about paying to ship water. I'm so over that!
 

ButterflyEffect

Well-known member
I think I got misunderstood. I use calmag..and I also use calnit and epsom salts too.
Either one of it will do the trick.
I agree that calnit and epsom salt is way cheaper than calmag.

But the ones that grow without using any of it,will probably have enough in the water so the plants haven't got a deficiency.
If you look careful at the first pics you can see little spots which look like calcium deficiency, but nothing to worry about..it's minor.
If my plants look like the ones from @Chuckeye I wouldnt change anything either, they look stunning.

My point was that, to really know what's going on, you need to know what's in your water and go from there
Agreed and good call on the leaf spots. That may have been a Ca def from earlier on since the leaf damage from a Ca def.
won't go away on old growth. That said, that's exactly why I want to get on top of this now. Calcium deficiencies, once they're visible, are already causing issues. I've learned to keenly watch for the signs such as lead twist in new growth.

I guess my only concern with a diy calmag is using calnit which has higher N than I'd like
 

ButterflyEffect

Well-known member
I think I got misunderstood. I use calmag..and I also use calnit and epsom salts too.
Either one of it will do the trick.
I agree that calnit and epsom salt is way cheaper than calmag.

But the ones that grow without using any of it,will probably have enough in the water so the plants haven't got a deficiency.
If you look careful at the first pics you can see little spots which look like calcium deficiency, but nothing to worry about..it's minor.
If my plants look like the ones from @Chuckeye I wouldnt change anything either, they look stunning.

My point was that, to really know what's going on, you need to know what's in your water and go from there
Forgot to add, my water had nothing as it's rain water. 20 ppm
 
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