Just bought Cal-Mag should I ease them on or go with the recommended serving?

WyoKush

Member
Hello and thank you for reading and hopefully replying, any input is welcome. So here's the situation i'm in... Its the end of week 4 veg and i'm doing my res change (running DWC). I noticed yellow vein's in my fan leaves which is an indication of Cal or Mag deficiency so I ran to the store and got some Botanicare Cal-Mag. I'm wondering if i should ease them onto it or just go with the recommended amount that their nutrient calculator for week 4? I am using it as a foilar spray to let them soak it up right away.

Thanks again and happy growing to all.
 

az2000

Well-Known Member
Yellowing between the veins is magnesium def. Brown/orange spots is calcium def. If you only have the former you only need to add epsom salt, maybe 1/2 tsp/gal. If you add calmag you'll increase calcium when apparently it's not needed.

IMO, the only reason to use calmag is if you use ro water which removes ca and mg. Then about 2-3ml/gal is sufficient. Or, if you have ca and mg def together.
 

WyoKush

Member
Thank you az2000 for explaining the symptoms of each deficiency and for the cheap tip. I've written it down and will definitely be using it in the future if I continue to have this problem. I am planning on upgrading and running R.O. RDWC after this go around.

Thanks again and happy growing.
 

az2000

Well-Known Member
Thank you az2000 for explaining the symptoms of each deficiency and for the cheap tip. I've written it down and will definitely be using it in the future if I continue to have this problem. I am planning on upgrading and running R.O. RDWC after this go around.
For ca def, it's not as easy to buy calcium at the local grocery store. I dissolve eggshells in vinegar, (<<link) breaking down the calcium carbonate into relatively pure ca. Should be more immediately acting because typical calcium carbonate products (antacid tablets, etc.) won't need to breakdown in the soil. And, it's not adding nitrogen like calcium nitrate does. (Nothing wrong with adding nitrogen. Just not what I'm trying to fix if I have a ca def.).

If you go hydro you'll probably want to buy bulk quantities of calcium nitrate to treat ca def. I'm not sure dissolved eggshell would be ok for hydro. It should be just ca. But, might have organic stuff like residual egg white, membrane, etc., that would promote slime growth. I don't know.

Just saying it's better to treat mg or ca def independently if they occur independently. And, if you go hydro you might as well buy calcium nitrate and then use HydroBuddy (google for it) to calculate how much epsom salt and calcium nitrate to use together for an optimum ratio. (You can even buy NPK in bulk and figure out your own amounts.).
 

BenRipped

Well-Known Member
I agree with az2000, calcium is great if the plants need it if not don't add it. I did some testing with the botanicare calmag and using it regularly with base nutrients at 2-3ml a gallon my test plants seem to be a lot more leafy especially between the bud sights. This may also have something to do with the N as well. Altho I've grown some chemdawg strain that needed like 4-5mils of calmag every feeding on top of base nutrients, but I feel that's more based on the specific plant and not a general usage of calmag. So stay away from it if possible, most times just add more base and will fix any calmag issues.
 
Top