We've had a lot of luck using Rid Ick (I think that pets mart is the only place that carries it[don't get ick attack, it's worthless]). It isn't as strong as copper (both in terms of treatment and stress to fish) and is more effective that hypo.... we had to use it in our 150g FOWLR when the fish that were too big to house in any of our iso tanks caught a nasty bought of the white dots. Didn't lose a soul.
Btw, it's malachite green and formaldehyde based if you want to look up the active ingredients.