I bought a new cory on Thursday. He looked healthy until last night when he came up with red veining through his tail and was dead by morning. As soon as the guy at Petsmart who's been helping with all my cory problems saw it, he said it was Septicemia. He suggested I use Triple Sulfa if I see any signs of the disease in my other two cories, but that bettas are more resistant to it and it's less likely that he would catch it. If worst comes to worst, is the medication safe to administer to a 10 gallon tank with 2 cories, my betta and two ghost shrimp? If it isn't, should I put the betta in a QT tank and treat the 10 gallon or should I put the cories in the QT tank and just treat them? The tank is cycled, 78 degrees, planted, etc.