I ran a Powerquad 96W CF over my 10G nano (when I had it) with good success. Fits perfectly on that size tank, and less of a heat issue that MH. I think most nanos are shallow enough to allow CF to get good light penetration to the bottom.
I used the 20" Coralife Aqualight. It was about $90. It is my refugium light now. Cheato REALLY grows under 96W of light, especially since the refugium is only 7" deep...
Anyway, I am rambling. Just wanted to mention the MH may not be required.....