To those of you who DON'T quarantine...

[naesco]

IMO there are a few rules you must follow.
1. Never buy a fish that you do not see eating. Dont be bashful. Ask the LFS guy to feed the fish and if he is not eating aggressively pass on the fish. The fish was just recently feed is not a good excuse.
2. Leave the fish at the lfs a week and than come back a see that it is free of spots, redness tears etcetera. Dont accept the fish unless it is 100% healthy, alert. Just as happy to you see as you to see her.
3. Acclimate the fish carefully. Close off the tank lights for two day to give her a chance to settle down with her tank mates and reduce her stress.
4. Feed garlic soaked food with a little selcon to avoid the possibility of ich or some minor bacterial/fungal infection.
5. Have a QT set up and ready to go just in case a problem develops.
Good Luck