I run 3 bags of chempure elite in my sump just before my return section, I am having a lot of growth and great colors on my sps, and all corals in general. Not sure how much the chemipure is contributing, but it certainly doesnt harm anything. I run it on every tank I own, from FOWLR, to LPS/Softie nanocubes, to my 75G sps mixed reef.