true the air stones alone will offer minimal water movement, but in the event that power is out for multiple days it'd be the most power efficient way to keep things alive, i was thinking more like the 12" long stone bars, 2 of those will keep things moving enough for survival......
the solar idea is brilliant and could work very well with a deep cycle battery
be aware that 12v dc to 110 a/c power inverters suck power and if loaded with a few powerheads may only last a day.....we'd have to do some math of the units getting driven off it.....