Which brand you using? There seems to be a lot these days. Searching for similar stories by brand helps a lot.
I too opted for the Red Sea system after bp's didn't seem to take care of all of the nitrate and phosphate. Even tipping the balance to add more nitrate, it didn't work. Then when I turned the flow up, there must have been some extra compounds being released because nitrate and phosphate were fairly high still and necrosis start to occur. (I was feeding on schedule everyday, and I've only ever attempted one brand, so that could have been the issue, but I've seen when dealing with bp's, they have a few unnecessary steps in degradation that can result in "sugar competition" with corals/symbiodinium... iirc)