So I have a 40gal breeder with a 29gal sump and have sectioned off within the sump a 6 gallon area that is being used as a refugium, roughly 11 inches cube. Right now I am just using a flood light to grow some macro, but would like to be able to grow some frags down there since the macro doesn't really grow that well anyways. I can also DIY stuff pretty well if you know of any good links.
So what would be a cheap way to add some lighting down there. I would like to go with some type of MH or T5s and less than $100.

It is only 11 inches deep so I'm guessing a 70W MH would be plenty. I really like the 70W Viper but it is too pricey.