Good luck. Did you already get the tank? The ATs are amazing, unfortunately my tank isn't big enough (125g), so I am going to go with my next favorite the powder blue tang. Like others have said, make sure you get a quarantine tank setup as soon as your display tank is. That way when you finish your cycle you can get your pair of clowns and start QTing them. 4-6 weeks is long enough to stare at rocks and moving water...No expert but heard it isn't advised to have two pairs of clowns in the same tank because they will squabble. Good luck!