Heres my setup:
tank 6'x2'x2'
4 rows of PCs, from front to back:
4 x 6500K, 4 x blues, 3 x 6500K, 3 x blues
all on electronic ballasts...
Been running for a year now... switched from NO actinics to PC blues... it really brought out the greens beautifully, when combined with the 6500Ks... the blues alone do not bring out any flourencent, just turns everything blue...
My corals include: a pink bubble, an green octopus, a green galaxy, 2 kinds of leather, a cup, a green favia, 2 sea whips, a red chili, a brown snake-skin clam, 2 BTAs, GSPs, and mushrooms of all colors...
All doin fine so far, n im pleased with the colours... MHs r the way to go but its too expensive n runs too hot, n the electric bill would take-off, plus a chiller in my tropical country... woosh!!! way too much moollas...
Growth... well the bubble has doubled in size, the BTAs r bubbling... dunno wat else to say about growth rates... i guess im just happy the corals openning up, n none r dying...
HTH...