Home made Cal-Mag vs bought

Hey everyone! Ok I’m asking everyone their opinion on this subject. Home made Cal-Mag verse store bought, is there a major difference. Does it matter which you use?

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I think most people don’t know how to make their own calmag. How did you make yours?

With ground up egg shells and vinegar…for the Cal. Heat egg shells until dark brown. Grind fine if you can. Add vinegar to eggshells. Let the react until vinegar smell is gone. I start with a 4/1 ratio. 4 vinegar to eggshell. Mag…I use teaspoon of epson salt. I’d appreciate any input from other farmers too!

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You’re good.

I’m about to test the same, how many days generally do you leave rest your mix of eggshells and vinegar?

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Fish has not posted for a couple years now.
Perhaps do a Google search for more info.

Sorry been away a long time. VA surgery went a little crazy. My body rejected all the pins and screws they had put in me. I had an allergic reaction to all hardware. I haven’t been able to grow( sucks major league).

After mixing the eggs shells with vinegar. After the initial reaction I will usually shake it up a couple times a day for about 2 days. It is basically ready after the initial reaction. I just feel a little more confident shaking up for a couple days. All the eggshells should settle in the bottom of the mixture.

Sorry about not posting everyone.


I’m sorry to hear that man, i hope all is going to end up well.

For the calmag eggshell issue, i put 25g eggshell in 0.1gal vinegar, i leave it like about 5 days shaking it few times a day, than i add it to to water in 1:30 ratio, it looks like it works.

Get well soon!

Bill ward has a video on youtube on how to make it very easy instructions haven’t tried it yet tho

I sometimes do the same thing to bones after a whole roasted chicken or t bone steak.To make calcium phosphate. The egg shells are mostly calcium carbonate. Bones of chickens and beef are mostly mineralized of calcium phosphate. It is essentially calcium + bloom food. I usually add the epsoms salt at the next watering. For some reason if I add it to the dissolved bone solution I end up with a precipitate. I believe it is calcium sulfate or the same as gypsum.

(Ca+(PO4)-3 and (Mg+2)+(SO4)-2 all in aqueous acid solution. I believe the precipitate is CaSO4. Anyway, if you add the epsom salt separately it does not drop out of solution.

When you dissolve the bones in acid the left over bones will be soft and rubbery. All that’s left after all the minerals are dissolved is the proteins like collagen. These I just toss into the compost tumbler to finish them off.

Sounds very interesting to me as my dogs eat a lot of beef bones and they left many around as they know tomorrow fresh bones will come on their plates…

Which acid solution do you use?

I use whatever I have. Vinegar is cheap and easy to get but being a weak acid it needs more liquid to dry bones ratio. Most hydro ph downs work well. But those cost more $. I like to go cheap. I even have used spoiled juice and day old coffee. Both have a ph of around 4-5. Nice and acidic. I have used the pickle juice in pickle jars even. I reuse old pickle and mayo jars to make my extracts. Or a bigger batch in a 5 gallon bucket.

Don’t pour the effluent right onto your plants. You have to dilute it with water first. I usually do 1:4 or 1:5 ratio. Like a pour off the l gallon (or so) liquid into my 5 gallon bucket and top it with fresh water.

I don’t do this all the time. Just if I have a plant that is in need of a calcium boost over what’s all ready in my raised beds. If it’s in flower why not add some phosphorus too is my reasoning. I have not gotten anything from the grow shop besides microbes boosters in like 3 years. I have in the last 20 years gone from chemical fertilizers and salts to 100%living soil depending on compost and ferments and char. I even make my own rock dust with my kids rock tumbler.

It’s less about a cause and more about self sufficiency. In case the winds of legalization shift for some reason. I remember the days cops would take your down your plates at the hydro store and follow you home. Like just for buying the big box of fertilizer and big bag of soil. Make your own seeds, soil, and fertilizers one season. Just so you know you can. Just incase you have to again. Sorry for the tangent. I am feeling quite irie.

@noddykitty1 glad to see you back online! I was beginning to worry about you as well as @CurrDogg420. Did you manage to get an outside grow going this year, or too busy installing tanks?
My outdoor autos, proof-of-concept self-watering wicking system worked, but I was too physically gimped to implement any guerilla grows of my clones this year. Ended up cramming 10 clones in my 4x4 tent (1 hermied, gone in 60 seconds!), and the 2 other photo clones outside I don’t think will finish before our torrents begin. One might take shelter under the hot tub gazebo, but the other is too tall for that even.
Anyways, glad to see you’re still kicking!

Thanks for the answer! In the meanwhile I did some research too and looks like I will go for vinegar as is cheap and is working, so good enough to me.

I try myself to avoid hydrostores as here winds of legalization are pretty far, cops do the same trick and even you are allowed a few plants, if they come to your house even is below legal maximum number they will still destroy it and you need to go to court and will end up not getting charged… but still, you lost your work.

For microbes i do kefir water, but this is going to be off-topic i guess