By now, your power is back on, hopefully, so this email is probably too late. But, in case it's still on -- you should be fine. I had a power outtage that lasted much longer than that. I put hot tap water into baggies and floated them in the tank. Since your tank is quite small, be careful about putting too much hot water into the tank and insulating it; you don't want to cook your fish. You can always do a partial water change with slightly warmer water every 4 hours or so.
With only 5 fish and 6 gallons, your system won't be too stressed, though you may end up with a mini cycle afterwards if your filter is turned off for too long. I did. Keep an eye on your ammonia and nitrite levels or do some partial water changes in the week or 2 after the power failure.
Some pet stores sell battery operated air pumps (for example, by Elite) that can be used during a power failure to aerate your tank. But lowering the water in your Edge should do the trick.