Thanks BryonNet the fish out and place it on a couple of paper towels folded over on a hard surface (table, bench, whatever). Give it a hard smack, or a couple. I use my hand, some prefer sticks. It is instant, no suffering, nothing. There is no other method as quick or humane, except cutting off the head but that is too much even for me. This method was rated "1" in an article on the topic in either Amazonass or Practical Fishkeeping a couple years back.
Those who advocate freezing, clove oil, and similar may find it less distasteful, but the poor fish is cognizant of what is going on. I don't treat any animal that way, not even a fly, it is whacked and instantly killed.
If you lived where I do, you would catch flies and torture them. During November/ December, I can't go outside during the day. They swarm all over you and crawl in places they shouldn't go. They literally drive you nuts so if you catch one and it's alive, you drop it on the ant nests around here. The ants drive me nuts too.I don't treat any animal that way, not even a fly, it is whacked and instantly killed.
You don't want to whack any fish that has dropsy. They tend to explode and it gets messyMy sibling had a goldfish with dropsy, so I managed to net it out (it was large, probably 5-6 in without the tail, and it was really bloated), put it in a couple of plastic bags, and smacked it against the garage. I don't know if that is basically what Byron's method is, to me it sounds like it.
Would you leave a human to die slowly and painfully if they had a couple of days left to live, or would you euthanise them with an overdose of morphine?If I were you guys I'd just leave them in a water body. tranquilizing them or whacking them is inhumane.