Is this in a 12g Nano Cube? If so, I have the model with the two fans (but still only 24w light).
Mine has been going for a couple months now. I added a
pulsing xenia first at mid-level, and its doing fantastic, I have tons of little one's popping up everywhere!
After that I added some zoas on the bottom, they're doing fine as well. Then I got some electric
green zoas, and am keeping them mid level so they get a little more light than they would on the bottom.
Just picked up a Fox Coral, which is a low light LPS. Doesn't have sweepers either, it's doing fantastic on the bottom of my tank, it is just huge now compared to when I saw it in the LFS. Awesome coral, my fiance's favorite as well.
And the tank is just about packed now, I added lastly, a Frogspawn, bright green and purple to the top of my tank. It was small in the LFS, but again, it has expanded almost 3x it's size since I brought it home. I like to think it's because I think I have very high quality water, even for a young tank (I'm adament about weekly 1g water changes).
Give those corals a try, especially the fox coral. Place it where you need to till it looks happy. It doesn't like flow, so keep it in somewhat of a dead zone too. GL! Here's an updated pic of my tank as well.