bought a pleco from petsmart. a couple days later my JD was covered in tiny white spots. went back to the store and noticed ick on the other plecos in the same tank. the manager told me that all fish have ick. I finally convinced the general manager that the other manager didn't know what he was talking about. they gave me my money back for the fish and free ick treatment. After asking how the filtration works for their tanks they told me that all the tanks were connected and used the same water. lesson = no more petsmart fish. haven't had a problem since.