I add it to my salt mix, so I know the new water change is correct and it also stops calcification {if thats what the white precp. is called}. Had bad problems with it before following this formula and my well water.
I make ca and alk. additions to my tank based on its needs alone. I,m guessing Bens products could be used mixed in fresh top off water the same as any 2-part.
Dan, I did use a standard measure cup. If I remember correct I broke down the measure I first got from Ben. I believe he mixed up a 40 or 50g barrel of water. So if one needs 37ml for a 5g mix, Put it in a measure cup and then see how many tsp. it is. I believe thats what I did. However, I see Ben now mentioned how many tsp,s are needed.
I just throw in 3 or 4 tsp. for a 5g bucket. Or a little extra if I notice the mag dropping. Same for calcium. Usually a level tsp. per 5g but sometimes less.
I have to go back and read what he said but looked like about 5tsp.of mag per 5g as long as the IO mag is at the mentioned levels.