Battery backups and heaters

[Oaken]

So considering that if the power was to go out during the winter and there was no heater how long would it take for a volume of 135 gallons to get to a deadly level

 

[Brad Miller]

Not a simple answer
Need more information
A few variables need to be known in order to even guess at the answer

A heat load of the building the aquarium is in would need to be done to determine the heat loss of the structure itself, (or general idea of the age, windows, square footage etc...)

Temp of the aquarium water
Temp of the spaces in the structure at the time of the outage
Temp of the outside air at the time of the outage

 

[Oaken]

Not a simple answer
Need more information
A few variables need to be known in order to even guess at the answer

A heat load of the building the aquarium is in would need to be done to determine the heat loss of the structure itself, (or general idea of the age, windows, square footage etc...)

Temp of the aquarium water
Temp of the spaces in the structure at the time of the outage
Temp of the outside air at the time of the outage

Just meaning a general rule of thumb. My only worry would be winter. Summer and others not my worry. The tank is kept at 80 degrees typically.