Cal Mag, what’s it do?

Hi, I used to do lots of indoors, just getting back into it. Sick of buying smoke.
Everything’s going pretty well, but I keep hearing and reading about people adding ‘Cal Mag’ what’s it for ?
I’m using Emerald Harvest now and following their feeding chart.
Would Cal Mag be beneficial ?

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Calcium and Magnesium, some folks use Epsom salt as a substitute, but my understand is Epsom salt is magnesium sulfate,it has no calcium in it. Cal mag is a calcium and magnesium supplement and has no sulfur in it. Aside from that cal-mag also has a little nitrogen and iron as well.

Calcium and magnesium are two of the three secondary nutrients required by plants, the third being sulfur. They are secondary in as far as quantities required for growth, not importance of function. Simply put, calcium and magnesium are necessary for plant growth and development and are easy to fix in the case of a deficiency. While nitrogen stands as requiring the highest levels in a nutrient feed, secondary nutrients calcium and magnesium only require about eight to 10 per cent of that amount. While their required levels are much lower, their importance can’t be understated. Calcium is important for strengthening a plant’s cell walls and maintaining its structure. The importance of calcium becomes evident when you see degradation of the leaves, which eventually shows up as discoloration and canker-like sores. When calcium is absent, the integrity of the cell wall falls apart. Calcium is not mobile inside the plant, so the plant cannot borrow from nearby areas to make up for local deficiencies. Instead, calcium depends on transpiration to reach its destination.


If you choose to use Cal Mag mix and use on water day only. @ArmoredGoat has you got you covered . yes Cal-mag is beneficial.


I added cal mag into my feeding schedule and have seen great results!