One thing that has saved my livestock (fresh and saltwater both) is judicious use of water conditioners such as Prime (Seachem or equivalent). Helps even during power outages. I 'm not sure if the lack of food is what killed your fish since most likely can survive a long time without food.
Personally I wouldn't do anything too drastic, maybe toss in a bag of carbon. Every 12 hrs dose it with a bit off Prime to keep nitrate in livable condition (until the bacteria recover). Use a syringe to target feed your fish, but i think you might underestimate their keen noses.