I want to have air circulate and use a $30 box fan with a non-hepa filter and to minimize power I have it on a timer so it’s on just a few hrs a day.
I also have some expensive hepa filters devices but they do not automatically turn on after a power outage. So I picked up some UPS power devices and to my disappointment, the devices drain the UPS system during significant power outages and subsequently fail to restart.