That's an interesting thought about the alkalinity.
But, Epsom Salts (which are magnesium sulfate) mixed in water are pH 5.5, according to Wikipedia, which is an acidic pH, not an alkaline one. And Epsom Salts always give me a candida flare up.
I'm quick to respond negatively to things taken on a completely empty stomach, if washed down with a lot of liquid, candida-wise. So maybe I'll experiment with different forms of magnesium on different days, in the morning on empty stomach, with full glass water, to see how each does for me. Some forms of mag are more acidic than others (I just looked that up on Science sites), so we'll see if it's the mag itself that causes the flare ups, or the acidicy or lack therof of the form of mag used.