even i f your lfs q's them, i would still(and do) have a q tnk, they really are life savers, and copper treatments may only hide some other problem, which may later surface in your tank, so i would still q them all(q tanks can be bought for very little, wal mart has specials on 10 and 20 gallon packages, that is all that you would need with that filter and lighting)
as for using copper, it is toxic, it does kill parasites, but it is also toxic to the fish, so i would not use copper, unless neccessary
there are other ways of removing parasites that are jsut as effective and are safer for the fish, like hyposalinity
i have to agree wiht anthem, quarentining with copper, kinda defetes the purpose, put them in it to make sure they are healthy only to subject them to unhealthy conditions