What do you do for power back up?

[reefbyremote]

I recently had to face the reality of a power failure. It only lasted 2 hours but it got me thinking about various scenarios...

I know the rate of oxygen depletion will be dependent on the bio-load but does anyone have any experience about how long one could go without power??

Also what does everyone else do? Or am I worried about nothing??

I am studying my options short of buying a generator. I am thinking something that can last for a few hours just to keep miniumum flow and this gas exchange in the tank. It also should not cost an arm and a leg!!

So far I have come up with:

a) A UPS designed for a computers. For $100 it looks like it is about 8 hours of back up on a koralia 3 or 4 powerhead. (Testing it right now!)

b) Penn Plax B-11 air pump, about $25 in Canada.

http://www.aquariumguys.com/silentairpump.html

I appreciatre everyone's feedback.

Thank you!