Well I've just stumbled upon this exact situation myself.
Currently my 5.5 has a hood with a screw-in 10w CF bulb. Like this one. DO NOT WANT.
Althought the solution Reeferton suggested would work, I'd like my fixture to look as clean as possible and mate right up to the 16" length of the tank.
AH looks like a sweet solution, however I'd rather not have to build my own hood for it as I can't retrofit this plastic hood. I thought Current had a possible solution, but I can't find it now, and it was a bit short.
I could get plastic cut to fit to top and use this fixture, but it's only 9" and 18 watts.
Hanging lights isn't a great option although it mightwork. I have a cat, so a hood or glass is mandatory on top.
Anyone have a "AIO" solution or am I better off just building a hood for the AH?
I put the AHsupply 2x13w in my 5g and it ROCKS. I love it. It is much brighter then my 24w piece of crap aquatrader light. I am growing HC, HM, Downio, and rotala rotundifolia very easily. I also dose EI and have diy co2 at around 50ppm.