Depends on a few things...Will you have a canopy above the tank? If you are, you might want to look at some t5 retro kits. I know I went this route, and ended up with 6 t5's under my hood. The one downside to T5's, you wont get the shimmering effect in your tank...I personally love that, and that's why I'm waiting for my new LED fixture to get out of customs, and find it's way to my house. I think you would be fine growing most things under a 6 light fixture, but I guess it all depends on how you stock your tank. Keep in mind also, bulb replacement will happen every 9-12 months, I think it costs me around $150-200. Also, the combination of bulbs that you use is endless...or something like that...and what one reefer uses and likes, isn't always the same around the board. If you ask "What bulbs should I use" you will open a can of worms around here. Best thing I can say, find a LFS that you like, and do buisness with (Helps if they like you too
), and see if they can set up different bulbs for you so you can see it with your own eyes. Hope that helps a bit...Oh, welcome to Canreef...this place grows on you!!!