How to euthanise fish

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nik_n

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After doing a lot of research on how to treat bloating, I have discovered that it usually can't be treated. My blue gourami is no severally bloated and I'm guessing its due to internal problems. I heard that it cause lot of pain to the fish. I took the fish out of my main tank and in a quarantine tank. I'm going away on holidays soon so I can't put the fish back in the tank and risk it dying in there because it would cause an ammonia spike and I won't be there to remove it. Because of this I have decided to euthanise it. I never did this before, but I want to use the most humane method so if anyone has any experience that would be very helpful.
 
Clove oil is effective, but a sufficient amount is required for the fish not to suffer. Since any quick death is preferred, another alternative is flinging the fish against a hard surface like a sink or concrete floor which will result in instant death. Some suggest hitting with a hammer or other hard object.
 
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Here is how I proceed with clove oil.
Dosage given for fish up to 8 cm.
What is needed:
- a container for 1.5 litres of water (to be adapted to fish size) with lid
- a small vial with a cap,
- a large net,
- clove oil.

1) Fill the container with water from the aquarium, catch the fish and put it in.

2) Pour 5 drops of clove oil into the vial, add very hot water to dilute oil, shake hard and slowly pour into the fish's container and lid it.
After 5-6 minutes fish will fall asleep.

3) After this time, put 20 drops of clove oil in the vial, fill it with very hot water, shake it hard and pour it into the fish's container all at once.

4) After about 15 minutes, if gills do not move at all, the fish has passed away.

If gills still move, repeat the oil/water mixture until the fish dies.

Good luck.
 
It's been a very, very rare occasion when I've had to euthanise a fish.
The idea of holding it and attempting to bash it against something hard seemed to fraught with possible mishaps and I felt I was more likely to simply injure an already stressed fish.
Placing it on a hard surface and hitting it's head with a hammer...see previous.
I'd heard of the clove oil technique and seen it in action, but knowing how clove oil can burn if you get it in your eye, for example, I doidn't like the idea of a fish trying to breathe its last in 'toxic' water, even if it did eventually fall 'asleep'.

So my method was to have a pan of water, in a rolling boil and to drop the fish in from a net. From my observation, that seemed to be a relatively instantaneous kill.
However, one unpleasant consequence of this method is that, unlike the scent of cloves, you get the scent of cooked fish. :(

Edit: I'll be getting tired of those who read this post, without reading my later one accepting my gross error, and go all self-righteous and show the :mad: face. Back in the day, I was misinformed and now accept that it was the wrong thing to do and I am grateful to @Essjay for my re-education on the matter.
 
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After doing a lot of research on how to treat bloating, I have discovered that it usually can't be treated. My blue gourami is no severally bloated and I'm guessing its due to internal problems.
Is the gourami still eating and what does its poop look like?
If it is eating well and doing coloured poop, then it could be just fat.

If the fish has stopped eating and did stringy white poop, then it has an internal problem and should be euthanised.
 
Here is how I did....
Dosage given for fish up to 8 cm.
What is needed:
- a container for 1.5 litres of water (to be adapted to fish size) with lid
- a small vial with a cap,
- a net,
- clove oil.

1) Fill the container with water from the aquarium, catch the fish and put it in.

2) Pour 5 drops of clove oil into the vial, add very hot water to dilute oil, shake hard and slowly pour into the fish's container and lid it.

After 5-6 minutes fish will fall asleep.

3) After this time, put 20 drops of clove oil in the vial, fill it with very hot water, shake it hard and pour it into the fish's container all at once.

4) After about 15 minutes, if gills do not move at all, the fish has passed away.

If gills still move, repeat the oil/water mixture until the fish dies.

Good luck.
 
Have you euthanized the gourami yet?

I agree that clove oil is the best way without violence. This is what I do (I eyeball it based on the size of the fish). I always use a zip top disposable bag and size it based on the fish, I will place the bag in a bowl or cup (again based on fish size) and fill it with some of the water from the tank. I will then add a few to dozen drops of clove oil and close the bag (being careful NOT to get clove oil on my hands or any fish equipment, you can wear gloves if you like, but should remove them after this step and put on new ones if you want). After the bag is closed (check it well) you want to violently mix the bag so the oil is distributed, the water should look milky. If the water isn't milky looking add a couple/few more drops of oil and repeat. Once the water/oil concoction is ready, reopen the bag and have it ready for the fish. This is easier if there is someone to help. Now you can catch the fish and place them in the bag, again not getting the clove oil water on the net or other fish equipment. Close the bag with the fish and remove air as you can. The fish may thrash a bit at first (like seconds at most), but will quickly go to sleep and then within a minute or two you should not see any gill movement. I also keep them in the bag for 15 minutes to make sure they are dead.
 
It's been a very, very rare occasion when I've had to euthanise a fish.
The idea of holding it and attempting to bash it against something hard seemed to fraught with possible mishaps and I felt I was more likely to simply injure an already stressed fish.
Placing it on a hard surface and hitting it's head with a hammer...see previous.
I'd heard of the clove oil technique and seen it in action, but knowing how clove oil can burn if you get it in your eye, for example, I doidn't like the idea of a fish trying to breathe its last in 'toxic' water, even if it did eventually fall 'asleep'.

So my method was to have a pan of water, in a rolling boil and to drop the fish in from a net. From my observation, that seemed to be a relatively instantaneous kill.
However, one unpleasant consequence of this method is that, unlike the scent of cloves, you get the scent of cooked fish. :(
Damn! If you ever need to euthanize me: please smash me with the hammer. Don't drop me into boiling liquid :oops:
 

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