I worked for Hyatt hotels years ago, and we had three restaurants that served TONS of fish. The best way to store fish for extended periods of time, is to keep the fish dry, (i.e. not soaking in water), try using large zip lock bags or commercial size plastic wrap is best...put the fish on the bottom, and LOTS of ice in the bag or on top of the plastic, changin it out as needed to keep ice, not water on the fish. Keeps it very cool without freezing, and will hold much longer.