If possible go to a bait store and get a battery operated air pump and airstone. I imagine that stuff is at a premium right now, but you may get lucky. If that's not possible, I would have a bucket and syphon hose next to the tank, and every 1/2 hour or so, I would drain 5g and dump it back in.
If the clean up crew is the only oxygen demand on the tank, it is possible that they could last for quite some time with minimal circulation.