here's what i have over my 72 gallon, works great!! if you want to start out cheap, get the 2 bulb model, then when the ballast goes out, or you think you need more light, replace the ballast with a triple tube model, and buy a little bit of wire and some flourscent clips! cheap upgrade!
I would definitely opt for a diy model. way cheaper and you can get better/customized results
here are a few pics of the light setup...cooling fans that i have installed in the hood of my 250... used regular plastic gutter to run all of the wire and floodlight bulb sockets mounted to the gutter to mount the flood bulbs.
small tanks cfl is fine... shop lights only if you are on a top roman budget. they are like the cfl really inefficient. they are not made to toss a lot of light into a small area but a wide area.