I have a two gallon hex, and i got two fancy guppies yesterday. it took about an hour to get them to the tank (which has been set up for a week) and i let the bag sit about twenty minutes before I let them in. I fed them a little bit and they seemed to be fine. I fed them a little more before i went to bed, and when I got up this morning. I came back this afternoon to see half their tails missing, and one was unable to stay upright. It died and i took it out. The other one wasn't swimming as enthusiastically as before, and after going out and coming back, he too was dead. So, does anyone have any suggestions?