That's gonna be all over the map.
How deep are your pockets?
You need the high power 3watt leds - some name brands LED's (CREE, Luxeon, Bridgelux)
Are you handy and like to DIY or want custom color choices? Check out the DIY resource thread in the DIY section for links to DIY kit suppliers.
On of our sponsors (ModAquatics) has a semi-diy module in that you can somewhat customize the colors/size to your needs and retrofit that into a hood.
Name brand fixtures:
I have (well just purchased) AI leds. Really cool - dimmable but limited to a white and blue fixture (no violet/uv).
I think the following two have some better color choices in that you can get some violet/uv type light. Maxspect Mazarra - dimmable , orphek - not dimmable, etc.