>>2112483Depends on where you live, here in Florida the fastest way to killing a fish is submerging it into slushy ice water. The fish drop into shock so fast that the pretty much make 1-2 wiggles before its lights out. I find it to be more humane that way but you need the right amount of ice and water and the right size cooler for the fish your keeping.
You don't want to have so much ice that you can't put your hand into it.
Do you don't want so much water that when you do put your hand in the cooler it's so cold you can't keep it in there I kill all my left over Shrimp the fast way.