If you want to have a reef tank, and want the ultimate flexibility. Metal Halides are the way to go, they are brighter, and give the beautiful shimmer effect in the tank. flourecents you will need more bulbs, and therefore more expensive to change them out when it comes time. I have a 250W and a 175W metal halide kit i can sell you for cheap, they work really well i have 2 250Ws im installing above my 75gal soon to be reef, hit me with an email and i can give you more info. But indeed MH is the way to go, i wish i would have done it a while ago. They are sooo bright and beautiful.