BoostLED has an all white bulb 7000k 5x3W with 60 degree optics, i was considering that. The reefing folk recommend 1 bulb for 12x12", can i get away with 1 bulb for 24x24" area? Considering its planted.
You would either need to get wider optics or raise the bulb higher to cover a 24x24 area. I would think the output would be fine, its just the coverage you need to worry about.
Or you could always build your own and save some $$