what lighting do you have? And you may wanna be carefull about a leather in a 24. I just got a 3 inch frag of toadstool from a guy who had it in his 24 nano...when i got to his place, he showed me the tank and i was amazed to see a HUGE toadstool leather that was taking up the whole left side of the tank and was actually starting to grow out of the tnak. He said he'd only had it 6 months and got it when it was about the size of the one he gave me. So be carefull w/those.
Pulsing xenia is a good choice tho imo. But also you can prolly get that for free from just about any reefer in your area...so check your local board to see if someone can spare it. Also greens stars are good, along w/kenya tree