Careful owners who wish to ensure the humane treatment of their fish before eating them have an easy solution: this variation on anesthetic used by vets for animal euthanization can easily be done at home without special equipment or administration fees.
Once mixed, carefully dissolve 12 drops of clove oil in water before pouring the solution into an appropriate container for your sick fish. Place it inside and wait until its gill movements cease; this usually takes less than 30 minutes and is an extremely humane way of killing sick fish that cannot be brought directly to a vet. Many aquatic life experts also suggest the "scotch method", similar to how aquatic experts administer treatment - often this involves placing sick fish into an oxygenated environment until its final rest.
Next, restrain the fish with something such as a tea towel and use an object such as a hammer to hit hard on its head, inflicting sufficient nerve damage that pithing or decapitation are no longer required; failing this, a quick stab in the brain using a sharp knife should suffice.
Bleeding fish is necessary to ensure its flesh remains fresh and edible, but should never be used as a means of killing. As stress may lead to slower deaths, this method can also be difficult for large commercial operations involving many smaller fish, as capture and restraint must occur simultaneously with stunning. New technology that seeks to be both humane and efficient may make mass fish slaughter feasible in the near future.
