i have just removed my glass catfish as hes just fallin to the bottom of the tank and the black skirt tetras keep attackin him, iv put him in a jug as i dnt have anything else is there anything i could add to put him down gently, hes got a massive lump on his throat and a red thing on his side the sooner the better
Make sure you are 100% about killing him before you do. Are you sure there is no hope?
If you decide it's the only way, you could either go down the clove oil method or the bag and brick method.
Get a house brick, place the fish in a plastic bag of some sort drop the brick directly on the fish from about 5 inches. Dead instantly, no suffer. Just try to keep the time out of water to a minimal.
James.