I have been under minimum lighting for some time now and have an RBTA, some mushrooms, Kenya trees, finger leather, pulsing xenia, and candy cane corals.
I just upgraded to duel icecap 660's and changed over to 2x72" (1x50/50, 1x10k) & 4x48" (2x50/50 & 2x14k) and left the 2 50/50 96watt PC's...