My first fish, Feather, has been horribly sick for 5 days. Without going into a lot of detail, after various meds/water changes, etc., I think it's his time. He's over 3 years old, so age may be a factor also. I can't bear to see him lying on his back gasping for air & not eating for another day. His blue color is almost white now. If I have the ability to decapitate his head, how do I know for sure that i have also killed his brain? I read i should use a pin, I guess as long as I enter it through his head, that will do the job? I can't believe I am even thinking of this, but I agree, this isn't about my comfort level, but rather, the quickest way to end his suffering. Thanks.