Jim when I reach CA at 420 and Alk at 11 i knew it was time to fail it back with at least ALK. Right now I am dosing ALK at 10ml per day and CA at 45ml per day. Alk has been stable now at 8.4 for over two week period. Mag has stayed at about 1300-1320, still dosing the same every other day. For me some of the corals tips whited out with the higher ALK. So made the adjustment. I will test tomorrow and make any other adjustments. I however did do the water change with IO and the ALK is typically around 8-9 dkh.
Jim lets hope you can stabilize so that your acro's come back.

Chip thanks so much!!