SPS Bleaching

[DSlater]

Has anyone run into problems with the Tailored Aquatics DKH Plus? We switched over from using C-Balance and within a week started noticing our SPS were bleaching out from the tips and also from bottom up. It was rapidly travelling down the entire coral (every day that I dosed it got worse) All our algae issues are gone - within a week all our rock that had a covering of algae are completely bare now... our LPS is also suffering a bit though not as much - just not as plump (our candy canes & hammer head). Softies seem completely fine. We run a 220g w/ an 80g sump with a fairly large bioload. We've turned down our lights as we were slowly ramping them up from installing in mid-January. We're sitting at 35% from about 65%. Mainly it's the acropora and Monti's that are having the most issues. Nitrates - 0, Calcium - 460, DKH - 8.5, Phosphates - 0.18 (high and need to change the GFO) & Magnesium - 1450. We were thinking that it was a combination of too much light and the sudden drop of nutrients. We now dose with our homemade mixture of Baking Soda (80/20baked) but the recession is still slowly happening. I've increased my feeding to twice a day as of 2 days ago and we've been feeding Reef-Roids every couple days. We also removed the filter sock last night and had unplugged the UV sterilizer 3 weeks ago. We're only running the skimmer & Phosban right now. I can't seem to win right now. I thought I had it under control but unfortunately the recession is still occurring - we're losing a lot of SPS right now. Has anyone had this happen? Any ideas? We're completely frustrated and at a loss. If we’re losing corals should we be running carbon as well? Any input is great appreciated! Thanks.