I am certain there is more to it!! I have had the "big 3" very stable for a year (verified by multiple ICP tests, Hanna checkers, etc.). I am seeing success with most of my corals, BUT the growth has been very slow and ~20% - 30% have died. Coloration on the remaining corals is less than spectacular. I recently rented a PAR meter from BRS and tuned my T5/LED combo lights to the right level (~350 PAR at the surface). I was not too far off on my light settings, so I don't expect a huge change. My flow is cranked up pretty high. I do weekly 20% water changes.
P.S. I spot feed my corals a combination phytoplankton, zooplankton, mysis, Rod's food, flake food and Tropic Marin pellets (I mix it up, spot feeding 3-4 times a week). I also dose Red Sea Coral Colors A/B/C/D.
Soooo so I'm not sure what else to do, but there must be something other than the big 3.