Right now, yes, you could probably keep mushrooms, polyps and xenia, but you may find that some things need to be placed very high up in the tank. I'd try buying a single mushroom (~$5) and see how it does. If it's reaching for the light, move it higher. Give it a month. Remember that you don't have a lot of margin as far as lighting excess to work with, so be patient.
The powercompact retrofit that fits in the eclipse hood will allow you to keep most softies with relative confidence that they'll have adequate lighting. It's way better than the NO lights you have now.
Take a while to decide what types of critters you want to keep (softies, LPS, SPS, clams, etc) and let that decide what type of lighting you get. If you dig softies, then maybe the retro will work out for you. Lighting can get expensive, so know what you want and get it the first time.
As a rule of thumb, 4-6W of PC or VHO lighting per gallon will work for softies and LPS (for a tank under say 24" deep). A Metal Halide setup (MH) will allow you to keep pretty much anything.
Ty
[ September 05, 2001: Message edited by: tyoberg ]