I have the 13.5 fluval evo. I have 2 DC powerheads that don't have a "stock" backup option (slw-10's). I am trying to figure out the best solution to getting gas transfer in the tank during a power outage, and everyone talks about backing up a powerhead. In the case of my nano, I'm using a sicce syncra silent .5 pump with 8 watts of power usage, & I believe the pump is AC. Also the return pump is the one causing most of the surface disruption. Would this mean that backing up the return pump is the best option? If so, how do I calculate runtime for UPS? I've been searching google and they come up with plenty of formulas giving me all sorts of different results, the need to calculate power factor, etc. Does anyone know how long a 600 va / 300 watt UPS would run this 8 watt pump for? What if I added in my 100w helio smart heater? Just curious if I'm able to run that on UPS as well since everything is so small in a nano. Also willing to look at other backup options, but UPS seems like the easiest route.