Well - I have to admit I had my doubts about not floating the bag, but it worked. It has been 24 hours and I just turned the lights back on and all of the cardinal tetras are alive and seem well. They are swimming a pretty tight shoal but I'm sure as they get used to the tank and the other inhabitants they will be fine. I still can't believe that not one of them died. I'll wait a week and let you know how they are. AA and everyone thank you for your help.