Here's the commie formula for producing a white-table cloth fish fit for a five star eatery:
1)) Give the fish a wood shampoo immediately after it's in the boat---don't let it flop.
2)) cut out the gills, gut the fish, scrape out 100% of the blood line. With your thumbnail (or water jet), force all the remaining blood out of not only the blood line but the individual veins going up into the fillets on either side of the belly cavity
3)) Belly-ice the fish (or keep a supply of frozen water-bottles in your cooler and insert them into the belly cavity after you gut your fish)
4)) stack the fish with the heavy ones on the bottom, teenagers on top, with generous layers of ice in-between the fish. Flake ice (salt or regular) is the best---plug the cooler with ice
5)) Open the drain, then chock the cooler so the drain is on the downward slope---codfather got it right---draining is the key----it's an invitation to bacteria to let the melted ice pool in the bottom of the cooler
As codfather also mentioned, commies typically will get 10 to 14 days of shelf-life out of their fish, provided they're properly cleaned, bled, belly-iced, layer-iced, then the cargo be arranged to DRAIN
If you want shelf-life on your hali, heed IFL's advice---leave them gutted but in the round. Only fillet the fish for freezing or for eating; not for storing in a cooler. I'd add the following--- if you're going to store a headed and gutted male hali for any period of time, reach back along the blood-line to the extreme rear of the belly cavity, then with your index and middle finger, get the nuts out.