Med Man,
Is your rock already cured or are you curing it? If you are curing it, you can either use low intensity lights, the lighting you would normally use for your setup: turned on for only a small period of time during the day, or no lights at all until the rock is cured. However, it is not a good idea to use full-blown high intensity reef lighting for 12 hours a day while curing, because it only increases the chance of nuisance algae blooms. The theory behind using a small amount of light is that it will help keep all of the living beneficial macro algaes and coraline algae from dying. Use too much light, and it will bleach your coraline algae, and increases your chances of an algae bloom while nutrients are at a peak in your system. The best way, however to cure live rock, (according to most aquarist) is to use no light at all until the cycling is fully over, and you are at no risk of an algae bloom.
ecoman,
You are on the right track. You probably do not want to use ordinary flourescent lighting, because it supports the growth of nuisance algae in your system. Specialized aquarium ligting is made to mimic normal sunlight, and does not support this kind of algae growth as much. It all depends on what kind of system you are going for when you arepurchasing lighting. If you are going FO, then normal strip lighting may be used. If you want a reef with soft corals, they will do fine in an aquarium with PC, VHO, or other similar HO flourescent lighting. If you want stony corals, then you will want to go for the metal halide lighting, which will also support all other photosynthetic corals. It isn't so much how many watts per gallon as it is what kind of lighting you need for what kind of system, butas a rule of thumb, I think it is about 5 - 7 watts per gallon for reef aquariums, as a minimum, but I cannot remember exactly.