's are the way to go, but not the cheap junk that's so abundant from china. This sort of ubiquitous rubbish has no coral growing capability at all.
If you are thinking about LED
's then this sort of thing is what you need to be thinking along the lines of...
Truly awesome lights, my LFS
has one on display/demo at the moment and they are beyond anything I've ever seen, he has two fixtures over a 250 litre tank being controlled by the controller box, gone are the days of supplemental actinics and the such, you can program the units to run any kind of cycle you wish, with a plethora of different colour mixes cooked up by the blue and white LED
Epic, I'll be buying some this year without a shadow of a doubt.