Can Increasing Magnesium drop alkalinity?

[Rcunning8]

So I have been on a mission to idealize my magnesium levels. Since switching to regular instant ocean from reef crystals for my monthly water changes my magnesium has been reading at 1200 when it used to be 1400. My tank rarely fluctuates from Alkalinity of 8.3-8.5 and Ca of 450. Last week I thought I would try to reach my target goal of magnesium and stated dosing magnesium throughout the week. Today I tested magnesium and was able to increase my mag to 1300 up from 1200 last week. My calcium today remains at 450 (the same as always) but my alkalinity dropped to 7.7 from 8.4 last week and this never happens ever. I am wondering if increasing magnesium can decrease alkalinity or is this just a sign that my corals picked up in growth and are just consuming alkalinity faster? It makes sense on a chemistry level (and with timing) that increasing magnesium would drop alkalinity. Both calcium and magnesium are 2+ cations and bicarbonate Hco3 is a -1 anion that dissociates into hydrogen anion h+ and carbonate co3 2-. normally one carbonate ion is consumed in the redox reaction of calcium therefore neutralizing the two positive charges on calcium and the negatively charge anion of carbonate particles. Also magnesium is right above calcium in the periodic tables which means they are very close to each other in the way that they behave in the general chemistry world. I am just wondering if anyone else has experience or if someone could post a link to some research in this regard. Thanks!

Ryan