Cal mag with tap water?

I read alot about EVERY1 saying cal mag this, calmag that…in every1s opinion, is cal mag necessary WITH tapwater? Or maybe only at start of flower? I also read it depends on led or not and led style light need it more then hid lights. Early on in my grow i tried calmag and im pretty sure the over abundance of it bc of tap water caused a lockout. Im just about to flip so i was wanting every1s opinion. I just dont wanna stress em in early flower. To be clear i am not using ro water…thank you all for your opinions/knowledge.

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If you are using coco. Yes, you will still want to use it. I haven’t really noticed any one using it with Soil. @Covertgrower @Myfriendis410 @MattyBear @dbrn32 could probably answer this better


Ya its soil. Ffof to be exact. Also battleing the ph drift from that…different topic though.

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@Hellraiser may be around as well

I use it in soil

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You use it while feeding with tapwater and soil? Start to finish?

Even if you have high calcium levels in your tap water, doesn’t automatically mean all of it is plant available. From there, the need for a calmag supplement would depend on the levels of calcium and magnesium in your media and/or base nutrients, and how much your plants are demanding. The fact alone that you’re using tap water doesn’t make much of a difference. I can grow in inert media and use ro water all day long and not need calmag, because my nutrient package provides ample amounts of calcium and magnesium. Doesn’t mean you could do the same with different products.


I see what u mean…just have not used it much and when i did it seemed like they did not like it. This was early on b4 neuts were started. Im using the trio and solubles.

I am trying to see how this works, i have a question, I want to ask of the Brains…so How much pure Silver Nitrate do you mix with pure sodium thiosulfate to How much water to spray plants to get them to make Pollen??? Female seed?

What was final concentration of your solution?

Half strength. 1/2 tsp p gallon

Maybe it was a fluke…bc my plants also got hungry at same time…om ffof ran out of neuts at 27 days. Believe it or not the tds was at 500ppm. 6 weeks i thought but no way. Ya so timing could have been quincodence but not sure. This is why i asked bc honestly idk and dont wanna piss them off.

My guess is you are probably right, wasn’t isolated to a small dose of calmag. I would use search bar and go through some topics on the soil you are using. See if you can pick up any tips that may help.

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