Advance warning: This post is about fish euthanasia. So, if you don't want to read a sad post, this one's not for you.

I had to put down one of my fish today. My sweet vegan SO doesn't particularly want to listen to me talk about fish euthanasia, so I thought I would blog about it here.

The fish in question was named Nemo. I don't ordinarily name my fish but this one came to me already named, by way of friend who was moving out of town and needed to find her fish a new home. So, Nemo joined my tank in 2008 and has been living there happily ever since. A few months ago she started changing color, with her scales getting slightly darker. I wasn't too concerned about this since she still seemed to be eating and acting normally. I figured this might be the fish equivalent of going grey, since she was getting up there in fish years.

Yesterday Nemo didn't come up to feed, and when I looked around in my (still green) tank, I found her near the bottom, floating at an odd angle. She wasn't dead, but she seemed to have lost the ability to right herself and was pale and not moving around very much. I thought it might be best to leave her since there wasn't any infection or anything that I thought I could treat, but today I saw one of the other fish picking on her in the tank. That's not a good way to go. I considered setting up the spare tank I keep as a hospital tank so that she could die in peace, but she seemed so listless and weak already that it seemed like euthanizing her would be the best option.

It's been a while since I've had to kill a fish, so I did some research on methods over at Wet Web Media. I wanted to make very sure that I was using a method that would be effective but not painful. I opted for using clove oil to anesthetize Nemo (since I had it on hand), followed by freezing. The combination of these methods seemed to be the best way to address the limitations of each: Some people said that clove oil alone was difficult to use because it was hard to tell when the fish was really dead or just anesthetized, and opinions were mixed on whether freezing a conscious fish actually caused pain. I used the clove oil first, waiting ten minutes or so until there was no visible movement, and then put the container in the freezer to ensure that Nemo didn't wake up.

I'm pretty sure Nemo died of old age (I'm guessing she was at least three years old, which is fairly old for a platy), but even fish deaths of natural causes still get me down. I guess it's inescapable part of owning any kind of pet, though.

So, RIP Nemo. You were a hearty little fish. Nemo is survived by one offspring, a small but fast orange male platy who's still alive and well in the tank.