I have to agree with Mike here; an anemone and 2 fish in a 5.5 is probably not realistic. I kept a BTA and one maroon clown in my 10 gal, but that tank had an external sump/refugium, auto top-off, and a decent skimmer. Still, every few months I had to give the clown fish away because it just got too big too fast. For a 5.5 w/o any external water volume/filtration, I'd consider maybe one tiny fish like a firefish, one shrimp, and some softies. You could light it with a single smartlite, I guess that's the P.C. you're talking about, but even one small PC will heat up that small a tank. I love nanos, but to be stable they need a VERY low bioload.