How To Euthanize Fish Without Cruelty

There are a few approaches that are popping up online that are just plain silly and downright cruel in my opinion.

Please do not use these approaches:

  • Throw fish on the ground to knock them out.
  • Flush them down the toilet while they are still alive.
  • Leave them in the water until they suffocate – it’s slow and incredibly uncomfortable.
  • Hit the fish on the head with a hammer that you can miss and create a lot of pain.
  • Place the fish in the freezer which is slow and can be debilitating for the fish.
  • Placing fish in boiling water is an excruciatingly painful way of dying.

I can’t believe anyone would think the latter had been an alternative, but I met him online.

Some people advocate decapitating the fish. It could kill them pretty quickly, but if you get it wrong it could cause a lot of distress to the fish.

how to euthanize fish

Therefore, unless you have expertise in beheading fish and understand that you are able to quickly cut the minds of fish altogether, I do not recommend this method.

Overdosing fish on prescription anesthetics is the best approach to make sure they don’t last.

However, these drugs are not available to people and many people do not have a local veterinarian who treats the fish.

So let’s discuss how to euthanize fish using objects that are easily accessible to the general public. This is a rather controversial issue that is endlessly debated on the Internet in aquarium forums.

I present to you what, in my opinion, are some of the best approaches to euthanize fish in your home so that they do not suffer needlessly.

From there, it is your responsibility to select the method with which you are most familiar.

Clove Oil


  • Painlessly puts the fish to sleep and then finishes them off.

The inconvenients:

  • It takes a while.
  • Danger of not fishing maybe not dying and waking up afterwards.

Clove oil is an essential oil derived from the leaves, buds and stems of this Syzygium aromaticum plant . The active ingredient is a chemical known as eugenol which has clogging properties.

Artizen Clove Essential Oil (100% Pure & Natural – Undiluted) Therapeutic Grade – Terrific 28g Bottle – Perfect for aromatherapy, relaxation, skin treatment and more!

Clove oil can be used to numb fish so that a minor operation can be done while they are sleeping.

However, if you leave the fish enough, the eugenol will kill them.

This is really a great way to painlessly euthanize a fish, but you need to make sure you leave the fish vulnerable to coconut oil for a long time .

Otherwise, the fish may appear dead, but it is only deeply, deeply bored, and effective in waking up.

Equipment :

  • Container to put your fish adapted to the size
  • Clove oil
  • 57 g jar or container with tight lid
  • Hot water
  • Medicine dropper
  • Air pump
  • Airstone
  • Overhead tubing

Measurements :

  1. Learn how much water is in the container you plan to use for your fish holds. You need to understand this so that it is possible to properly dose clove oil.
  2. Fill the container with enough water for the fish to rest comfortably.
  3. Set up the airstrip, pump and airline to find constant bubbles in the water. This will allow the clove oil to spread through the water column.
  4. Half fill the small pot / container with lukewarm water.
  5. Use a dropper to run the clove oil into the jar. You will need 0.5 ml (about 10 drops) per liter of water in the huge container. It’s about 2 tbsp. Teaspoon (teaspoon) per gallon.
  6. Place the lid on your own jar and shake it vigorously until the liquid becomes more sterile.
  7. Roll up the fish and put it in the container.
  8. Gently pour the acrylic coconut mixture into the container with the fish.
  9. The fish will calm down, then lie down gently, turning the belly.
  10. Leave the fish in the container for at least an hour to make sure it has expired.

Read Also: Ammonia Poisoning Fish – How Serious Is It?

Alka Seltzer


  • Very quick way to kill fish
  • Alka Seltzer is readily available

The inconvenients:

  • The fish is struggling temporarily

Adding Alka Seltzer can even quickly euthanize a fish. When you drop the tablet into water, there is an instant chemical reaction involving uric acid and sodium bicarbonate (baking soda) which induces the rapid formation of carbon dioxide (CO2) bubbles.

The CO2 rapidly increases the oxygen in the tank, killing the fish.

I have used this method a number of times over the past few years and can attest that it works very, very quickly, in a matter of minutes from my personal experience. I let the fish out of the water for 10 minutes or more to make sure that it is exhaled and that it will not revive should put it back in an oxygenated environment.

I’ve never had a fish revive, but I’d rather be safe than sorry.

The downside of this way is that the fish will struggle temporarily. Some argue that this is proof that the fish is in some distress before they exhale.

I cannot provide you with complete scientific evidence that fish lasts or does not. But I could tell that in a few minutes the fish completely stop moving and breathe out.

So, I certainly don’t believe there is prolonged suffering. I really leave the fish in the Alka Seltzer water for 10 minutes or more to make sure it has completely expired.

It’s probably overkill, for example literally, but it makes me feel so much better.


  • Container to put your fish adapted to the size
  • Alka Seltzer tablets (8 tablets per gallon / two tablets per liter)


  1. Fill the container with water from the tank, Internet fish and put it in the container.
  2. Insert 8 tablets per gallon of water.
  3. The tablets will sparkle fiery as they dissolve, the fish will simmer for a few seconds and float to the top of the water.
  4. Leave the fish in the container for at least 10 minutes to make sure it is expired.

How to Eliminate Dead Fish

I know a lot of people think it’s enough to throw the fish down the toilet, at least the little ones.

However, I am not advocating this. Rinsed fish can end up in local waterways.

Then they can transmit the germs, parasites or viruses that killed them to native fish. This can have catastrophic effects on local fish populations.

I would suggest putting the fish in a plastic bag and throwing it in the trash instead.

It’s best to be careful and protect wild fish if we can.

Leave a Comment