"Dose Nitrate" That's always the answer around here isn't it? lol
Feed the fish more and also feed the corals. That's a great way to increase growth and nutrients in a bio-pellet tank. Also, run carbon in a reactor that huge leather is prone to putting toxins in the water that can irritate the SPS. Last thing, I'd lower the T5's down to a few inches off the water and what bulbs are in there?
I feed my fish more than anybody I know, and I've got 9 fish in a 45g cube at the moment -- feeding more doesn't increase anything in some tanks. My biofilter is way too strong, so sometimes 'feed more' doesn't work. But dosing nitrates does, as it's some biofilters are too intense. Even with the skimmer off, my no3/po4 has to be dosed.