[Elut]

Hello everyone !

I'm an expat living in Korea, and also a homebrewer.
Lately I've been struggling to find homebrew supplies to treat my water and increase its sulfate, sodium, chloride, calcium, magnesium and general hardness.

After searching for weeks, my wife found several chemicals on Korean websites.
But I have a few questions:

1- Is that thing Di-ammonium Phosphate?
Unfortunately, I never was a good student in chemistry classes in my youth, and since I started my homebrewing activities, I strongly regret it... But I remember reading somewhere that "Ammonium Phosphate, Dibasic" and "Di-ammonium Phosphate" are the same thing.

The industrial aspect of it raises the following question: Is it too pure, or can I use it, as it is, as a yeast nutritient (DAP) ? Don't I need to "cut" it with something? Is this thing food grade?

2- Also, if we find CaCO3, CaCl2, and/or other compounds conditioned as chemistry supplies in their row powder form, can I use them as brewing salts/water profiles adjustments without any risk?

Thanks in advance for the help !