My fishroom is in the upstairs of my Cape cod house. It’s heated by 1 electric oil heater which works perfect every winter every year. This year I’m in Ohio and as everyone knows insane cold temps hit. My fishroom dropped to 58 degrees, luckily all my tanks stayed with a degree or two of 78 which all me Co Op heaters are set but ran constantly. I added a second 1800 oil heater and the room would get to about 62 degrees and my aquarium heaters had to do the rest. Luckily everything is good other than the crazy electric consumption.