i bought four minnows. they looked healthy in the tank, there were very few dead in a tank of at least 50. one had a broken spine and died shortly after i got home. the lady handled them roughly so i think the injury was from that. another one was hyperventilating and floating at the top. i expected that one to die. the other two seemed just fine, they were swimming around and even looking for and nibbling on a pond fish pellet. i cleaned the container thoroughly, it had nothing in it but water from their bag and about a third of it room temp from the tap. the same water my snails do just fine in. i was getting them used to the water in that. i left the room for barely a half hour. came back in and all of them were dead. not three hours after i brought them home. and the container was new, it was one of those plastic ones you keep them in for temporary/travel. is there anything i could have done differently? could it have been stress or injury?