About 12 years ago my fish room was a converted garage. I had 40 tanks or more set up mostly for breeding wild caught African Cichlids. The room was only partially insulated and I had a vent to cut down on the humidity so it was a little tricky to heat in the winter. I had a couple heaters that worked pretty good most of the time. Here in Ohio the winters aren't too bad usually, but there are half dozen or more days that drop below freezing. So I had a bigger heater as a back up for those days.
I had three groups of tanks that were on sumps together and the rest of the tanks were on a blower and sponge filters. So the two heaters, 3 pumps and the blower were all on one circuit but that pretty much loaded it. I had a second circuit for power tools and for the big extra heater.
I forgot to check the weather before going to work one day. I was evening when I decided to check the weather on the internet and noticed, yup it was going to be below freezing that night. Called the wife, who was pregnant with my first child at the time, and told her to plug in the extra heater. I figured no big deal, she had done it before.
Finished up working my 16 hour shift and by then the weather was near blizzard. Took over 2 hours to drive home a normally 40 minute drive on the highway. I was so tired, I got home and went to bed.
I know this is a long story, but the WTF that I felt in the morning when I woke up and found the power out in my garage and near frozen tanks, you probably can't imagine. My wife had plugged the heater into a power strip on the circuit with all the pumps and other heaters. Blew the breaker.
This is when I learned that my wife who remembers everything and is way smarter than I, goes a little bonkers when she is pregnant. Hormones or whatever. So for the next two children, she wasn't allowed to touch tanks until they were born (her rules not mine).
Yeah I nearly quit keeping fish, but I didn't blame her. She felt horrible and blamed herself, but I should have checked on them before going to sleep.