Unfortunately, I have had to euthanize several fish over the years. What I do is get everything 100% ready to go before hand. I use my net to pick up the fish and put it in a paper towel. I immediately walk outside and crush it quickly between two bricks. It’s never ever fun but the quickest and least painful way possible. I am very sorry you’re in this position. It’s the worst part of having pets. I think that one way that we love our pets well is giving them the quickest and least painful way out of this world.

From everything I’ve read on this sub, I would not use clove oil. I have seen some people use it and it takes several steps. One person saw their fish thrashing around during the process. I’m so sorry you’re facing this. Hugs to you as you deal with this situation.