Maybe the insurance companies could sue the government if this was indeed the case. I would really like to see the bad policy makers go to jail or get hit with huge fines.
The aquarium was likely very constant (otherwise the fish would die, they tend to be extremely sensitive to variations, especially rate of change), but the surrounding air likely was not.
Those fishes can stand an interval of temperature if changed slowly. A main question to check would be if the thermostat was deliberately lowered by the owner in the previous weeks to save energy