My Royal Gramma has major ich and has affected my clown as well. Couldn't catch it to treat it. My clown seems to be more resistant. I won't be getting another (similar)fish anytime soon.
14 gal biocube salt
1 orange zoo polyp colony, 2 toad stool (small), 1 umbrella leather (large), 2 pulsing xenia, 1 star polyp colony, 7 blue mushrooms, snails, pep. shrimp, 3 blue legged hermits, 2 onyx percula clowns