^^^ im in the same situation as you are. a month ago i was running biopellets, carbon, and gfo + i was only fed the tank 3 times a week. the tank itself was only setup since january and a lot of my sps were pastel colored with very little polyp extension.
recently i removed the gfo, cut back on the carbon and changed the feeding schedule everyday. its been around two weeks and im just starting to notice more polyp extension and deeper colors.
so imo, i think you should feed a little bit more and cut back on some of the nutrient removers as they may be stripping your water with the nutrients your corals require.