It really depends on if we are talking about the easier to keep photosynthetic gorgs, or the non-photosynthetic gorgs which will die within a year(thats being generous) in most peoples tanks regardless of the light or what you try to feed them.
I keep a handful of different photosynthetic gorgs that do great on the floor under 250 w 10k xm's.
I have also tried a handful of different non-photosynthetic gorgs over the years and I have eventually killed them all. Note-I never wnet way out of my way to feed them either, so im not saying it cant be done, but more often than not they die in the average hobbyists tank.
i keep mine under 110w VHO's and 400watt 20k's. so far so good ;p
I'm planning to set-up a relativly small tank, 20g w/20g sump, reg flourscent lamp with a large focus on natural/biological filtration and feed very heavily with a variety of food. I wanna keep all non photosynthetic gorg's and sponges. I might even have an auto doser for some of the food, like a kalk drip.