Hi Mand,
Nice little trees you got there. I can see why you hang out here.

I agree with you and Towel. Flourescents just don't have the proper lumen(think that's the right term) output to reproduce sunlight, which is what has to be done to grow indoors. GroLux is fine for houseplants and fishtanks but MJ doesn't fall in to that category. And for sure the fixtures will have to be upgraded to handle MH or HPS. I'm pretty sure they draw a lot more current than even high intensity flourescents. So make sure all of the wiring and circuits can handle the load as well. Don't know about weed but the german reef aquarium enthusiasts actually use fiber optic skylights to get direct sunlight to their little corals and such. A clever idea that requires no electricity but is very spendy.