Lighting 180G (72x24x24)

[Slick Fork]

I'd also agree with 3x250watt MH OR 3x175 would probably be ok to. I ran 175 watts when I had my big tank running. It was 22" high, and if I was picky about where I put things I could keep anything I wanted, high light stuff in the top half with low light stuff closer to the bottom.

Give some thought to building your own "fixture" it's quite easy and can save you a lot of money as well as give you some interesting ways to customise.

Whatever route you go pay extra attention to reflectors as those are critical to whatever light source you choose.