Diy calcium magnesium suppliment - calmag

Star Dog

Star Dog

Well-Known Member
Milky Weed said:
I feel you man. I’m always playing with nute levels it seems as my humidity changes or the temp changes. It’s hard tuning it in when your trying to push the light even alittle bit in my experience.
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It's possible it could be light related, bits look fine others look flat.
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I've since moved them out of the clone tent after re potting.
 
G

Gumdrawp

Well-Known Member
PeatPhreak said:
It reacts in a bad way with several different elements that are commonly found in nute solutions.
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EDTA is also a registered fungicide, so you really don't want to be using it in a biologically driven grow long term or in large amounts. As a foliar it may have some ipm benefits though for powdery mildew, especially since the solution for calcium EDTA should be basic too.
 
Milky Weed

Milky Weed

Well-Known Member
Gumdrawp said:
EDTA is also a registered fungicide, so you really don't want to be using it in a biologically driven grow long term or in large amounts. As a foliar it may have some ipm benefits though for powdery mildew, especially since the solution for calcium EDTA should be basic too.
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Aw shit. I guess that’s why all my mycorrhiza seemed to have died. My fert has a few EDTA chelated elements in it.
 
G

Gumdrawp

Well-Known Member
Milky Weed said:
Aw shit. I guess that’s why all my mycorrhiza seemed to have died. My fert has a few EDTA chelated elements in it.
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It would depend on how much EDTA is actually in the solution, good organic soil is a really good filter. Even chlorine from your tap water is largely irrelevant, I believe they did a study and water that's roughly 10ppm chlorine only affected microbes in the top half inch of the soil before binding with other things in the soil. Most treated drinking water is below 10ppm. 4ppm is the general guideline for most water, and the further from the treatment plant you are the lower it will be unless it's treated with chloramine. I would imagine EDTA is similar and it'll grab onto something else and bind up before it gets too deep.
 
Milky Weed

Milky Weed

Well-Known Member
Gumdrawp said:
It would depend on how much EDTA is actually in the solution, good organic soil is a really good filter. Even chlorine from your tap water is largely irrelevant, I believe they did a study and water that's roughly 10ppm chlorine only affected microbes in the top half inch of the soil before binding with other things in the soil. Most treated drinking water is below 10ppm. 4ppm is the general guideline for most water, and the further from the treatment plant you are the lower it will be unless it's treated with chloramine. I would imagine EDTA is similar and it'll grab onto something else and bind up before it gets too deep.
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Yeah that’s what I was worried about, I’m in peat doing Soiless drain to waste hydro. Anything “beneficial” seems to be real fragile from my short experience.

Hopefully it’s still there doing it’s thing, underneath the surface.
 
TheGreenPanther

TheGreenPanther

Member
roidrage152 said:
I used to use GH calimagic, or Botanicare CalMg with my reverse osmosis water, for deficiencies but it was getting real expensive, so I searched for alternatives. I can't vouch exactly for the science behind what I did, but I can verify that my plants didn't die, and they also seemed to not have Cal or MG deficiency.

Basically I took information from various people who have already done similar, and somewhat modified it in different ways. Basically the major brands of nutrients based on their bottle labeling got their calcium and magnesium from things I had trouble finding, or seemed too dangerous for me to want to have mailed to my house. The major brands of Cal/Mag supplements have Calcium/Magnesium/iron chelate. So I'll tell you whats in mine, how much to use, and why I chose the amounts. I mixed the chemicals with my own RO water. The qtys that I purchased could make like 100+ gallons I think.

Magnesium Sulfate (Epsom Salts) - This can be purchased online, but I bought it from CVS for like $2. You can find it in many drug stores and stuff, it's considered a plant nutrient on its own, and it's used as bath salts and other things.

Calcium Nitrate - I purchased this on eBay. I got 5lbs of it for $14.00, and turns out I bought way too much. Primarily a fertilizer additive though it has some other uses. Seemed pretty harmless to buy online, and was easy to find.

Chelated Iron - Iron EDTA - This guy I don't know much about. I found some on eBay for like $15, though I've seen it in many forms. The one I used was actually a powder. I think the powder is for commercial sized fields of vegetable crops, but someone had made tiny packages of it to sell on eBay. I think the nutrient companies are selling water soluble iron chelate with nitrogen now, which would probably be what I buy next time.

Now to figure out the proportions I used an old formula by "FATMAN" from a different message board and plugged it into Hydrobuddy a nutrient calculator to figure out the weights. The one problem is that the PPM vs the Weights FATMAN recommended didn't match. So I basically just plugged his PPMs into HydroBuddy, and used those weights to make my mixture.

fatmans Cal-Mag

PPM
Nitrogen 200
Magnesium 120
Calcium 259
Sulfur 160
Iron 10.00

I plug these PPMs into HydroBuddy and the results it gives me are so:

Magnesium 120ppm
Calcium 259ppm
Sulfur 160ppm
Iron 10.00ppm

Per 1 Gallon of water:
IRON EDTA : .291 grams
Calcium Nitrate: 5.8 grams
Magnesium Sulfate: 4.607

Please note that these amounts are pretty tiny. I used a pretty accurate scale for this and made a gallon. Next time I plan to make a 5 gallon batch. I feel like it could be more accurate if I could work with larger qtys of these chemicals. Another side note, mixing Calcium nitrate and Magnesium Sulfate is supposed to create Gypsum. So I made sure to completely dissolve my Calcium nitrate in my gallon of water before adding the Magnesium Sulfate or Iron Chelate.

I am not a scientist, and I honestly don't know how to work Hydrobuddy that well. I have been growing for some years now, though I don't consider myself a grand master or anything. I did go through 1 gallon of this mix with a fairly large crop. I used approx 1 teaspoon per gallon of water with my regular nutrient schedule. (I use General Hydro 3 part + some supplements). I added this CalMag mixture at least 70% of the time that I watered. I would normally just add it every time, especially since its so cheap, but sometimes I was in a real hurry or something or paranoid about my experimental mixture.

I can't give you a guaranteed analysis or anything, but I can tell you this. My plants grew pretty much the same as if I had been still feeding the name brand CalMag. And my plants didn't seem to have deficiency in Calcium or Magnesium. I'm making some more, and I'm going to keep using it. I'll post if something changes, but I would love to hear input from people smarter than me.
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Why not just make some anhydrous MgSO4 from epsom salt by heating it in the oven on broil for a few hours until it looks like chalk (dissolves much easier) and as for the Calcium portion you can dissolve gypsum CaSO4 in phosphoric acid, making it water soluble. Gypsum is just plaster of Paris. There you Have it, Calcium Sulfate and Magnesium sulfate(CalMag) with a boost of phosphorus, though you'll have to regulate the pH of the calcium solution after dissolution with a little KOH and there you get a boost of potassium. It works, I do this in DWC, you just have to be careful of the ratios, otherwise you get precipitates. I.e., don't overdo anything, especially KOH. You add 2 TBSP the CaSO4 to a 3 gallon bucket add phosphoric acid dropwise until the plaster dissolves then you can pH Up with KOH, (but not enough where you cause the plaster to precipitate out of solution), because it will be fairly acidic.
 
OldMedUser

OldMedUser

Well-Known Member
TheGreenPanther said:
Why not just make some anhydrous MgSO4 from epsom salt by heating it in the oven on broil for a few hours until it looks like chalk (dissolves much easier) and as for the Calcium portion you can dissolve gypsum CaSO4 in phosphoric acid, making it water soluble. Gypsum is just plaster of Paris. There you Have it, Calcium Sulfate and Magnesium sulfate(CalMag) with a boost of phosphorus, though you'll have to regulate the pH of the calcium solution after dissolution with a little KOH and there you get a boost of potassium. It works, I do this in DWC, you just have to be careful of the ratios, otherwise you get precipitates. I.e., don't overdo anything, especially KOH. You add 2 TBSP the CaSO4 to a 3 gallon bucket add phosphoric acid dropwise until the plaster dissolves then you can pH Up with KOH, (but not enough where you cause the plaster to precipitate out of solution), because it will be fairly acidic.
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That's so much easier and cheaper than going down to the store and blowing $20 on enough CalMag to last most home growers 5 years! rotflmao.gif
 
Star Dog

Star Dog

Well-Known Member
It cost me a tenner for 1.25kg of epsom and 1kg of calcium chloride, according to my calculations I've enough calcium for a fiver to make 10,000ltr at 100 ppm, I don't have a stock solution for magnesium but I'm working on it, regular branded calmag seems ridiculously expensive by comparison to buying the ingredients.
 
OldMedUser

OldMedUser

Well-Known Member
Star Dog said:
It cost me a tenner for 1.25kg of epsom and 1kg of calcium chloride, according to my calculations I've enough calcium for a fiver to make 10,000ltr at 100 ppm, I don't have a stock solution for magnesium but I'm working on it, regular branded calmag seems ridiculously expensive by comparison to buying the ingredients.
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I can never use up a litre of CalMag before it goes bad so I don't need enough to bother having enough stuff to make enough to last me a century. Just because something can be done doesn't mean it should be done.

I'm getting into making STS for re-sexing girls to make fem seeds and could not for the life of me source silver nitrate so I made my own. Just happened to have a small bottle of conc. nitric acid laying around so went to the post office and bought a .9999 silver coin for $20. It weighed 8g and I got 12g of AgNO3 out of it. Found a chem supplier in Ontario and got 500g of sodium thiosulphate anhydrous for $22. Purolator charged me $69 more to deliver it. I was about to make my own sodium thio as I happen to have some conc. sulphuric acid laying around as well but getting the other chems for that was more expensive than buying it once delivery was tacked on.

Now I have enough of that stuff to last me a century but making the silver nitrate was a necessity. I would have bought some of that if I had found it.

AgNO304.jpg

Hold your breath for this part! :)

AgNO303.jpg

AgNO305.jpg

:peace:
 
C

Chain'r up Chip

Member
OldMedUser said:
I can never use up a litre of CalMag before it goes bad so I don't need enough to bother having enough stuff to make enough to last me a century. Just because something can be done doesn't mean it should be done.

I'm getting into making STS for re-sexing girls to make fem seeds and could not for the life of me source silver nitrate so I made my own. Just happened to have a small bottle of conc. nitric acid laying around so went to the post office and bought a .9999 silver coin for $20. It weighed 8g and I got 12g of AgNO3 out of it. Found a chem supplier in Ontario and got 500g of sodium thiosulphate anhydrous for $22. Purolator charged me $69 more to deliver it. I was about to make my own sodium thio as I happen to have some conc. sulphuric acid laying around as well but getting the other chems for that was more expensive than buying it once delivery was tacked on.

Now I have enough of that stuff to last me a century but making the silver nitrate was a necessity. I would have bought some of that if I had found it.

View attachment 5116012

Hold your breath for this part! :)

View attachment 5116013

View attachment 5116014

:peace:
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Tried CS?
 
OldMedUser

OldMedUser

Well-Known Member
Chain'r up Chip said:
Tried CS?
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I've been making CS for 15 years but never bothered trying it on the plants. Might try watering a female plant from early in veg with it and see what happens for shits and giggles but being a retired chemist STS has more of an allure. :)

Was reading an article about injecting some silver nitrate just under the skin of the stem can turn a branch or a whole plant male depending on where you inject it so that's an experiment for another day.

Waiting now for some auto fem seeds to ripen on a couple of Mazarilla plants. Will be growing some of those outside this summer. Hoping to find a few on the pollen donor girl for some S1s. Have 4 strains about to go into flower now and will be getting clones and spraying a branch on each of the mothers to get pollen I can use on the clones later. Pink Kush, GG#4, Cherry Noir and an all CBD girl, called Earth Lover that I already have a few from the first attempt at STS but want more of her.

:peace:
 
xtsho

xtsho

Well-Known Member
Anyone that bothered to read the first post of this old thread should know that if you wanted to make calmag using calcium nitrate you would need to use magnesium nitrate and not magnesium sulfate as listed in the recipe that was posted. Calcium nitrate and magnesium sulfate combined make calcium sulfate or basically gypsum which is not water soluble. If you look at the ingredients for calmag that uses calcium nitrate you'll find that the other ingredient is magnesium nitrate as the 2 nitrates can be mixed together.

You can mix calcium nitrate and magnesium sulfate together and at first it will appear fine. After awhile though there will be a reaction and you'll end up with a chalky substance on the bottom of the container which is calcium sulfate. They can be mixed together in small amounts in a nutrient solution but you can't make a stable stock solution with them.
 
speedwell68

speedwell68

Well-Known Member
So what are people's opinions of using Epsom Salts and Calcium Chloride? I was going to use 3ml (5g) of Epsom Salt and 6ml (13g) of Calcium Chloride in 5L of water, along with my normal nutrients.
 
TheGreenPanther

TheGreenPanther

Member
OldMedUser said:
That's so much easier and cheaper than going down to the store and blowing $20 on enough CalMag to last most home growers 5 years! View attachment 5115489
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It is, because everybody already has pH down(phosphoric acid), pH up(potassium hydroxide) and a huge (I believe 25lb) bag of plaster of Paris costs $20, Epsom salts Cost $4 for a 5lb bag at CVS, where you'll almost never run out and it adds the -SO4 anion which promotes the production of secondary metabolites. The entire process takes 3-5 minutes, I do it with every water change. With Calmag $20 only get's you a watered down liter and the thread is about a DIY Ca & Mg supplement, so I don't see the reason for the sarcasm.
 
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