We have a very unhappy goldfish (a blackmoor). He has had various illnesses over the time we have had him including a major bout of fin rot (they did eventually grow back). Over the past month he has spent all his time floating still or lying on the bottom of the tank.
Dh cleaned his tank this morning and he is currently in another bowl, lying on the bottom and completlely listless.
Would it be kinder to just let him die? And what would be the most humane way?