Bagging fish for transport or auctions is very important and should be done properly with quality materials. It is essential that we insure the safety of the fish and the integrity of the bags used. The cost of bags is considerable, as well as the environmental impact from the use of oil and landfill volume. Wise use of our quality fish bags, and possible reuse of them can make sense.
HOW TO BAG
How do we properly bag fish? Most important is to get 2/3 to ¾ of the volume as air, and the rest water. This is necessary because the air holds much more oxygen than water, and considerably more oxygen will be available to the fish by diffusion at the water surface. I have the bag with the fish in it supported in a pan and open the bag to get as much air in it as possible. Then quickly grab the top 2-3 inches and close it to trap the air. Twist the bag top tightly leaving about 2 inches twisted. Then bend the twisted part over and use a rubber band to secure it as its base. Use tough, high quality rubber bands that will hold up and pull them tightly as you secure them, giving a tight seal. This allows a knob or handle people may pick the bag up with that will not release. Double bagging is often done, especially with larger fish and those with spines (e.g. cichlids, catfish, etc), giving the most security from bursting or leakage.
The reasons I prefer to tie the bags with rubber bands rather than just tie the bag itself at the top is because more bag is available to hold air, and they are easier to reuse. Reuse of bags can be done if proper care is taken. I will always rinse a quality used bag out thoroughly, check it for leaks or damage, and let it dry out. If any diseased fish or suspect water was contained, the bag is thrown away. If you buy and sell a fair number of fish, bags can be a sizable cost. I have even repaired some bags that have a single small leak. A small puncture hole can be found by placing water in it and closing the top under pressure and water will squirt out the tiny hole. Mark the spot with a marker and dry it out. A 1 inch square of clear Scotch Packaging Tape placed and pressed over the hole will securely fix the leak and will not be visible.
We are constantly bombarded with messages to save the environment. Properly bagging fish to keep them healthy, and reusing some bags to protect the environment is not a bad idea.