Could always go T5 too..
However, under a 10G tank, if you were going to do all SPS
then i would suggest a 150w Halide. I think for softies and some LPS
a 150 would be pretty intense over a 10G. Unless you hung it pretty high above the tank. I would say go with a 70w Halide over the 10G tank. You could keep anything you wanted and if you kept the light high above the surface of the water you wouldn't bleach any corals.
You could definitely do LED
's too.. and your corals would fluoresce like crazy.