Chlorophyll b is not present in corals - only chlorophylls a and c1/c2. I have a thread stickied in the lighting subforum that covers spectrum and photosynthetic pigments of corals and clams.These so called "high end" companies are not even putting half the effort they could be into the science behind the growth and color of corals. Spend a few minutes to learn about the PAR/PUR of your reef tank lighting and you will quickly see what your problem may be. It's not so much how much light you have as what kind of light you have. You need to measure PAR/PUR, compare it to the photosynthesis curves, see where the chlorophyll A and B values are at and try to match them.