Battery Backup and Pump Size

[ArizonaReefer]

The power has gone out in my area a few times this week and have been able to use a battery operated pump.

I have a good size UPS and want to run a Hydor Koralia pump off it.

Would like to get the lowest wattage pump that would still be enough to keep my fish alive. I figure the lower the wattage the longer the pump will last on the UPS.

The tank is 48x24x24

Is 400 gph enough?

Choices are:

400 @ 3.5 Watts
600 @ 9
850 @ 10
1200 @ 12

[Bonneville08]

The UPS should be rated in watt hours. Divide the rating by the number of hours that you think power will be off. This will give you an idea how many watts you can safely run. Sorry this does not answer your question directly, but it should help you choose a pump.