By design, Part C should not raise anything, including magnesium. Just offset the alk and calcium. That I get. But in the BRS instructions for their Pharma Hybrid Dosing, they make it sound like they intend the magnesium part dosed in equal amounts. Which struck me as wrong.IIRC, Lou at TM has said there usually isn't enough magnesium in the Part C to use it to bring levels up. This is why BRS has the magnesium supplement as well. You use a stand alone Mg additive to get your numbers in line, then part C should help you maintain it. Not always though. Depends on your system and how much it consumes
They need to fix that, and specify the Part C mixing amounts in milligrams instead of 4 scoops.
Other than that, it's a great improvement on basic 2 part.
Dennis