Not only do they know they sell diseased fish, but it seems they all of a sudden up and closed. I cannot confirm that yet, but I did stop by and they weren't open when they were supposed to be. I bought one fish from them and because I trusted what they told me (that they QT) fish, it wiped out my entire tank because of velvet. I have heard other people claim the same thing. If they are not closed or they reopen, don't waste your money.

