In The Tank

What do people use as a battery back-up for fishrooms? Do folks use a gas generator? Does anyone use a power station (portable or not) for their home and fishroom? The following is a review on Anker Solix F3800 Plus, which seems to be a good option:

https://www.cnet.com/home/energy-and-utilities/this-portable-power-station-can-do-the-work-of-a-tesla-powerwall/