Rebalancing parameters

[iceman86]

Hello, I'm having some issues getting my parameters in check again after I've been away from my tank for a month.

My system is 400 gallons ULNS sps dominant. While I was on holidays my doser went a little crazy on me.

I came back to these parameters
Alk 6.1
Cal 500
Mag 1340
Po4 0.02
Nitate 0
Potassium 390

I slowly raised my alk back to 7.3 (usually keep it between 7-7.5) which in turn brought my calcium to 490 and magnesium to 1410.

I stopped dosing calcium and magnesium to bring them down but nothing moved. I then raised my alk to 8 which in turn brought calcium to 480 and magnesium to 1360.

I can't raise my alk anymore because I'll start betting burnt tips or bases on the sps. I there any way I can bring down the calcium on its own to rebalace the system?
This has been going on for 3 weeks now.

Thanks in advance