Trouble keeping Mag level steady

[tom obrecht]

I have an sps system that has been up for roughly a year. I'm having difficulty keeping magnesium levels above 1100. I do binweekly to 3 week water changes and use reef crystals mixed to 1.025. Part of the gravity number is due to Mag chloride and sulfate of which I add to the new saltwater in amounts of 2-3 cups each. I mix 25 gallons of water at a time for water changes. I also add B ionic magnesium 2 times daily as well. I can get the Mag level higher if I dump a lot of Mag chloride in the system but it never seems to stay
I'm wondering if there is something I'm missing in keeping higher and steady Mag numbers? I have kept reefs for many years and have always had low Mag numbers so it's nothing new. I'm curious if anyone can see an issue of something I'm doing wrong?

 

[bertoni]

Have you double-checked the test kit? What does the freshly-mixed saltwater measure? I agree that something seems to be very wrong.

 

[tom obrecht]

I will retest the new saltwater. Test kits are brand new.

 

[zsuman101]

try a more balanced salt mix