putting fish in quarantine doesn't stop ick -- it just stops ick from being in your main tanks. I got a little pleco from an unnamed LFS in Rockville (coupon = free pleco) two weeks ago. I grilled staff person -- how long have you had him? any problems? etc etc. All assurances. Sure enough, quarantine tank came down with ick a few days later. Fortunately, I'd been acting as if the tank was contaminated even before it was confirmed, so no cross contamination. Did salt and higher temps and ick now gone. Will continue for a few weeks in the just-to-be-sure mode . . . no deaths, although the rainbow who is currently inhabiting the quarantine tank looked like a goner for a few days.