My husband and I had 4 fish and a shrimp, we had to travel for a week and came back to 3 white decomposed bodies of fish and one, I guess, leftovers of a body... Yet, the shrimp was still alive! Now we came back and found the central AC broken and I assumed the heat killed them, but the temperature of the aquarium is 25 degrees Celsius only; tank size is 75L. We've had 2 fish for over a year and the other 2 were like a month old; also, we had an auto feeder working, so they were fed for sure.
Now, what could be the reason they all died together?