Kalk dosing help

Im looking into dosing kalk. I know BRS sells in in bulk but dont you need to add magnesium also? Which one? Magnesium sulfate or chloride? Im going to be dripping it in my sump from a gallon jug. And also how much of each is mixed in the one gallon of ro water?

 

Ok I read into it a little further. I take it as though you need to bring calcium and magnesium levels up to where you want then start dosing kalk to maintain these levels. Am I understanding this right or am I way off?

 

You mix mag sulfate and mag chloride for the magnesium dosing. I really don't know much about kalk but from what I think I've read it doses Cal and alk.

Imo I looked into it too a little and thought I was just better off dosing alk Cal and mag all separately.