Is it a 20H or a 20L?
I currently have a 20L and love it. And you can pretty much have just about anything except sps. I have a few pieces, their colors aren't fading, nor bleaching, but they just don't have the light to grow at the rapid rate they should.
Lps does absoulutely fine though. I have several, claustrea, favia, and some porites. Tons of softies, xenia's, zoa's galore, leather coral, green & yellow polyps and mushrooms.