If you have a saltwater fish tank, what fish will you get first?

I really enjoy looking at clownfish (yes, the Nemo variety) and they are one of the easiest and most popular fish to keep in marine aquariums. I would love to get some (together with their symbiotic sea anemones) as soon as I can afford a marine fish tank.
A friend who is in the aquarium business suggested a tank of at least 110L minimum for a small shoal of them, along with other species. What is strange is that there is only a single large female and male pair in every shoal that mates to produce offspring. The rest are all juvenile males. When the dominant female dies, the male changes sex to become female and the next largest male takes his place and all the other males move up the hierarchy. Really interesting mating habits!