I use a big industrial battery (size 4D; actually two connected in parallel) and an inverter to power my Tunze circulation pumps. I have a DIY setup which makes it kick in automatically when power is lost. I do not power the main pumps or heaters or lighting as they would deplete the battery too fast and overload the inverter). This setup can keep the main tank circulating for days without power.
My plan would be to heat the room via a wood fireplace if needed in the winter.
Short of such a system, some battery operated air pumps are a good choice (along with plenty of batteries).
http://www.drsfostersmith.com/fish-...attery-operated-air-pumps/ps/c/3578/3669/8044