Good info. With over 100 tanks, I decided on a different avenue to cope with power losses. I installed a Generac 15kW automatic natural gas backup generator. I liked it so much that I also installed a 12kW system on the house.
I live outside of savannah, ga and have been searching stores all day for a few more air pumps. I went to a dollar general for new batteries and they only had one 2 pack of D batteries. Lesson learned? Yup, don't wait until the last minute. Have everything on hand and ready to go for these situations.
So my power went out and I wasn't sure what to do. So I purchased a mattress air pump from a sporting goods store. Then cut the DC power cord and attached a AC connector to it. Then cut another AC connector and attached it the car battery and used an extension cord to move the pump around the house to all my fish tanks.
If your tanks are close by or u don't care about lugging a car battery around, you can just cut the DC cord and attach it to the car battery.
You will also need to buy some hose and tape it to the pump. This put enough air to power my 300gallon it was crazy strong cost me 14 dollars. If you want to get real froggy you can pick up solar panels for the car battery.