Why such a high magnesium demand?

[Salty_Box_Reef]

I have a 120g mixed reef that's mainly sps but all small colonies or frags. I am trying to get my levels all dialed in but my magnesium demand seems awfully high to me. It drops from 1350 to about 1200 in three to four days.

I am dosing brs two part with alk around 9.2 and cal 420.

 

[Downbeach]

I would get a second opinion on the test. I had a reasonably heavy load, ~ 285mL daily(combination of kalk/Randy's recipe #1), and never had to dose Mg, with bi monthly WC's keeping it ~ 1300-1350 ppm. It sounds more like a testing issue.

 

[rock_lobster]

Mine is very high as well goes down 10ppm per day in the softies tank. Though yours looks a bit too high to be real.

 

[Randy Holmes-Farley]

I have a 120g mixed reef that's mainly sps but all small colonies or frags. I am trying to get my levels all dialed in but my magnesium demand seems awfully high to me. It drops from 1350 to about 1200 in three to four days.
.

Cannot be anything except testing error. Actual demand is at most 1-2 ppm daily. :)