I went on vacation for a few days, and when I came back I noticed that all of my fish (dwarf gouramis, lemon and cardinal tetras, blue paradise gouramis) were almost WHITE and were not swimming around at all. We then noticed that the heater/thermometer in our tank had literally blown up- there was a big hole in the side and glass was all over the bottom of the tank. As soon as we took the heater out and did a water change, all of the fish were fine again- except for one of our dwarf gouramis who finally died today. We did not know that this could happen, and are pretty upset at the loss of this fish. We are guessing that maybe it was next to the heater when it blew up and he never recovered from the shock. Has this ever happened to anyone?