The Coralife fixture in the link I supplied comes with a 6700K bulb, so there will be no need to buy another bulb. If you decide to go with the coralife, it is a standalone unit that should not be used with a canopy.
You can either lay it on top of a glass top (these run around $12-$15), or mount it using the plastic legs you can buy as an accessory ($7-$14, depending on if you get the adjustable legs). If using the legs, you have the option to keep an open top, or you can still use a glass top if you have escape artists or are worried about evaporation.
I think both solutions are pretty similar in price, so it comes down to whether you are a Do-It-Yourself'er or not. If not, go with the Coralife; you will be pleased. If you are a DIY'er, ahsupply seems to be the highest-regarded source for aquarium lighting components and their reflectors are top-notch.
Last edited by turbowagon; 03-22-2006 at 11:04 AM..