How much clove oil to euthanise a goldfish?

[lurcherlover]

One of my gran's fancy goldfish (she has three, all quite elderly) isn't looking well...he has a tumour and is starting to look extremely depressed. I'm thinking his days may be numbered. I keep tropical myself and am used to using the clove oil when necessary to give an ailing fish a humane end, but obviously the amount needed to kill a tetra isn't the same as for a fantail (I'm guessing he's about 8cm long, not including tail). How much clove oil will I need to do the job properly? With tropicals I mix the oil with tank water in a little bowl and put the fish in and death is instantaneous - I'm assuming the same method will work with goldfish? Poor old fellow

Oh, that's sad :( I had to euthanise my favourite goldfish a few years ago, I'd had him since I was a student and I cried buckets.

Yes, the method is the same. Well, I usually use the clove oil to put them under and then use vodka once they are unconcious but you can OD them on clove oil. You'd need a fair bit for a bigger fish. 10 drops should be enough to knock a large-ish goldfish out. I normally shake it up in a jam jar with some tank water and then pour it into whatever the fish is in.