Doing just what you did. Clean up, organize, plan, cut fabric, use my treadle. You got to get a treadle!
As far as your fish are concerned, depending on what you have. Tropical, semi Trop or fresh water. My larger than hand size gold fish made it 9 days without filtering two years ago and last year they went for a week without power too. We loose power more than average and know to keep a good supply of the stuff we need on hand.
I just kept replacing water every day. GF are very sturdy and can withstand a bit of "stress".
peace