HIGH CALCIUM and Magnesium. PLEASE HELP

[Reefadiction]

My 180gal tank crashed 7 months ago and been recovering since. In the past 5months all vital para are good. But 3 weeks ago Calcium and Magnesium slowly climbed.Calcium from 1300 to over 1500 and Magnesium from 1350 to just under 1500. Only running skimmer and reactor is disconnected.
Current parameters:
Ph 8.0
Nitrate 1 to 2
Phosphate under 0.03
Alk 8
Calcium over 1500
Magnesium 1490
Salinity 1.024
Temp 80f
Can high Cal and Mag bring ill affects to sps or even soft corals? If so how can i bring it down with out water changes. I did 25percents water change and it brought the Cal and Mag down by roughly 5percents. But this large water change give my fish ick. Any advices is greatly appreciated. Thanks guys