Why did all my fish die on the same day?
When I came home today, all the fish in one tank were dead. Some of them were old and it would make sense that they would be dead but some of them were only a few months old. The filter was running and the power didn't go out and turn the filter off for a long time because all the fish in another tank are still alive. I just want to know what could have possibly happened to kill them all so I don't make the same mistake again.