confusion and help

[daddy01]

Hi All,
I am new to reefing, and I am also behind the times..I started a saltwater in the 70's but then saltwater was a new field and I threw a couple of hundred $$ down the toilet in a month so got out.
Any way the hobby has gone though some drastic changes since then, so I started again in Aug.
I have a book "Marine Invertabrates" and have started a saltwater FOWL but now I am changing to softies and LPS' my tank has been running since Aug 4,2006.
My tank is 30X12X21 inches with live rock which brings it to apporximately 24Gal tank +-.
The inhabitants are Clown Damsel and FireGobie and a Frogspawn. I have compact flourescent (Aqualife) 130W light fixture. All my parameters except for Nitrate are good my nitrate isat about 25PP using salifert tests.
The livestock I want to have the book says my tank isn't sufficient size wise, yet I read here that some people have smaller tanks and have them?
What exactly can I have?
Here is what I am thinking of
Pearl Bubble
Brain coral
Frogspawn (I have)
sun coral
Ricordia
and some other of these types is it feasable?
Jim