vibriosis- best drug?

[MarieK]

I have a 1 yr old juvenile clown with what I suspect is vibriosis, just noted 2 hr ago, behavior was normal earlier in the day. It is listless, not eating, frayed fins. It is with 2 other juveniles that look healthy. No new fish, no new stressors- they are in their grow out-bare tank. Only thing I have a home this time of day is formalite 2 which I went ahead and dosed. If this fish lives or even if it does not live, should I treat the tank with an antibiotic-erythromycin, amoxicillin or augmentin?- (Cipro might be hard to get with the anthrax scare.) I figure before adding an antibiotic, I should do a hefty water change to dilute or get rid of the formalite 2. Any input would be appreciated.