What size tank are you working with? The clownfish will most likely pair up, as if you buy two small ones, one will turn into a female and become dominant. Just make sure that whenever you use something to treat your tap water, have it add as little things as possible to the water. So, things like Jungle Safe Start and API Stress Coat will cause the fish to suffocate due to the dechlorinators depriving the water of oxygen. Things like Tetra Aqua Safe are good to use, since they don't add anything major to the water, just remove the harmful minerals and such. For my fiancee's saltwater tank, he has a single ocellaris in a 20gH and he has green star polyps and palys. He also has macro algae, which the clownfish will host in. Hopefully your saltwater tank will do very well!
125gal African Cichlid
Great Dane and Doberman Pinscher [Harvey and Astro]