u can run clowns with just about anything outside of large predators.
and x2, start with 2 only.
they should both be small and the same size. both will be male (all clowns start out as male). they will pare and one will become the dominate (dominance hierarchy) and change into the female (will grow larger). crazy stuff..thank goodness humans are not like this...well they might be for some couples!! haha
when your tank matures (water is stable for months at a time etc) you can get a bubble tip anemone and the 2 clowns will host in it (more than likely).
clowns are one in handful of reef stock whose complete life cycle we can replicate in captivity. fun stuff.