K-Holed
Fishaholic
i've only had to do it twice in ten years but i place a newspaper at the side of the tank catch the fish in a net and put it on the newspaper, flip the newspaper over the net and just squash it quick and hard, 2 seconds max from catching it and death, not mentally the easiest but quicker than any other method. neadless to say throw the net.
I think you hit the nail on the head there. I think it's partly what's best for the fish and partly what's best for the owner. Personally I have no problems destroying a fish by whatever means seems quickest and least drawn out for the fish, but I can see that there are some that would find it hard to destroy a fish in some ways.