How To Euthanize a Fish: The Humane Methods




How To Euthanize a Fish

Sharing is caring!

Though it should always be regarded as a last resort, euthanasia is sometimes necessary. If our pets become sick or injured beyond recovery, we, as pet owners, have difficult decisions to make.

When deciding which method to use for euthanizing a pet fish, it’s important that being humane is at the forefront of your decision-making process.

All too often in TV shows, movies, books, and other media, we see the narrative spewed that the best (or only) option for fish euthanasia is being flushed down the toilet. This couldn’t be further from the truth. Not only are there better options out there, but this option is one of the most inhumane.

So, how to euthanize a fish humanely?

We’ll take you through the three truly humane options below…

Do I Need To Euthanize My Fish?

Remember when we said if our pets become sick or injured beyond recovery, we as pet owners have difficult decisions to make? It’s important that we emphasize that euthanasia is an option if and ONLY if recovery is not possible. 

A healthy fish should be every fish keeper’s top option. You should strive to provide your fish pet with a good quality of life. There are treatment methods that can treat different diseases, including both contagious diseases and bladder diseases. 

Luckily, there are many symptoms and signs of a sick fish. According to these include “loss of appetite, weakness or listlessness, loss of balance or buoyancy control, floating upside down, or ‘sitting’ on the tank floor, erratic swimming, staying near the water-surface or piping (‘gasping’ or mouthing for air), scraping themselves against objects, and clamped fins.

Many of these symptoms are treatable through various medications and do not need to spell the end for your pet. Injuries, however, are a little trickier. These treatments are available in health food stores around the world. 

There are some injuries, such as damaged scales, eyes, or nipped fins, that most fish will recover from. However, other more serious injuries may be fatal. When in doubt, always go to the vet before considering euthanasia.

Alternatives to Euthanasia

There may be other reasons to consider getting rid of a pet fish that don’t include sickness or injury. Getting a new fish that may be more aggressive, moving, or other big life events may have you changing your mind about owning a fish.

In any of these cases, it’s important that you know your options.

  • Pet Stores– Pet stores are often a great starting point when you want to get rid of a pet fish. And depending on the type of fish you have and its age and condition, you may even make a bit of money! 
  • Donate- Donating a fish to a doctor’s office or school is another great way to get rid of a fish. While you’re less likely to make money this way, it may be tax deductible, and you’ll feel great about donating to a good cause!
  • Reach Out to Friends/Family- Because fish are so low maintenance compared to other pets, it’s very possible that you know someone who’ll be willing to take in your pet on a temporary or permanent basis.

What To Do Before Euthanasia

You may still be wondering if there is anything else you can do to make your fish’s life just a little bit better. And the good news is there is!

You can provide comfort to your fish by following a few simple guidelines:

  • Excellent Water Quality- This one may seem self-explanatory and common sense, and it is important for your fish throughout its entire life, not just the end. However, dying fish are extra sensitive to most things, and it may not be a bad idea to test your water quality and clean it as necessary. (Be sure you know what pH your pet requires).
  • Removal From Tank- This is as much for the comfort of your dying fish as it is for the safety of any other fish you may own. Not only do dying fish prefer to be secluded, but they might also carry germs or diseases that can endanger other fish.
  • Increase Water Temperature- A slight increase in your fish’s water temperature may also be comforting. This compensates for the lack of heat they are putting off by swimming and playing energetically.
  • Be Quiet- Have you ever seen a “Do Not Touch Glass” sign at a pet store and wondered why? That’s because fish can become stressed out through vibrations that are carried through sound that humans are not aware of. One of the easiest things you can do to comfort a fish is to provide them with a peaceful and quiet environment.
  • Watch Their Diet- Be careful not to overfeed a dying fish. This can cause discomfort from being bloated if the fish eats everything you feed it, or it could cause the food to go uneaten and create dirty water.

Humane Methods of Euthanizing a Fish

How To Euthanize a Fish

If you’ve concluded that euthanasia is the best option for your pet, we have a few different recommendations for humane methods. We’ll discuss the pros and cons of each.

The Veterinarian Method

A veterinarian method is a great option for those who don’t want to put their pet down. The veterinarian method ensures that your fish will have a painless death via anesthetic injection.

However, the cons of this method are also something to consider. A typical amount that a veterinary clinic would charge for fish euthanasia services ranges from $50- $150

The Clove Oil Method

Clove oil is a great method for euthanizing fish. It is highly recommended for its peaceful nature, as the clove oil acts as a sedative and puts the fish to sleep.

Using this method, it is highly likely that your pet will not feel any pain, though that fact cannot yet be proven. This method is also extremely cost friendly as clove oil is commonly found at grocery stores for less than $10.

To use this method, you will need to follow only a few simple steps:

  • Transfer your fish to a smaller container.
  • Mix together water and several drops of clove oil in another small container. Then stir the mixture. (Do not add clove oil directly to fish water).
  • Add the mixture to your fish’s water and wait a few minutes for them to fall asleep.
  • Once your fish has fallen asleep, you should add a few more drops of clove oil to complete the process. Note that additional drops may be required for larger fish.

Overall, the process is quick. It should take no longer than half an hour to be completed. If after half an hour has passed, you are still seeing movement, just add a few more drops accordingly.

The Baking Soda Method

Of the three methods that we find to be humane, the baking soda method is our least preferred. This is because some pain occurs during the process. However, many people chose this option because all that is required is baking soda and water. The baking soda method is very convenient for people who are unable to afford the veterinarian method or are unable to obtain clove oil.

Similar to the clove oil method, the baking soda method can be completed in a few simple steps as well:

  • Mix together 1 tablespoon of baking soda and 1 cup of water.
  • Add to your fish’s water.

This method causes your fish to pass out before experiencing the effects of carbon dioxide intoxication. It is far more humane than directly exposing your fish to carbon dioxide, as doing so would cause the fish to suffocate to death without passing out.

Methods To Avoid

There are a few misconceptions about humane ways to euthanize a fish. The biggest of those being the flush. Fish owners must recognize the harm and unnecessary pain they will cause their pets by using some of these methods.

Flushing Down the Toilet

Flushing a fish down the toilet is an extremely inhumane method of euthanasia. This is an example of the “out of sight, out of mind” mentality being at play. If you only knew what you’d be putting your pet through, you’d never even consider the flushing method.

Flushing a fish down the toilet is not a guaranteed way to kill them (at least not quickly). Likely what will happen is that your fish will be violently transported through the pipes and drainage systems only to die in a sewage dump eventually.

Blunt Force

Blunt force, also sometimes referred to as stunning, is another inhumane way some people have tried to euthanize their pet fish.

This method typically delivers a calculated blow to a fish’s skull between its eyes. More often than not, this method is used by fishermen. If done properly, it can be a quick and painless way for a fish to go, but the risk far outweighs the reward.

There is no guarantee that one could do this method properly every time. And there is little room for error as it goes without saying how cruel it would be to beat a fish without killing it.

The Vodka Method

The vodka method works by poisoning the fish. It places a fish in vodka-diluted water (1:4 ratio), and the fish suffers alcohol poisoning until it dies. This method is one of the most controversial it can’t be proven that the fish will experience pain. However, it is not instantaneous and, therefore, not recommended.

The Carbon Dioxide Method

The carbon dioxide method directly introduces carbon dioxide into the fish’s water. It is another of the most inhumane ways to euthanize a fish, as it essentially suffocates the fish to death.

This would be roughly the equivalent of taking your fish out of the water and waiting for it to die.


Whether you choose to euthanize your fish or you find them dead in their tank, the disposal must be handled properly.

Many believe it’s okay to flush a dead fish down the toilet. However, just as you should not flush a live fish down the toilet, you shouldn’t flush their body either. This could cause many problems as septic systems are not meant to handle fish.

Luckily, there are plenty of safe methods to dispose of a dead fish.

The first step will always be to remove your fish from their tank. This is especially important if you have multiple fish, as you do not want to spread germs or diseases.

When removing a dead fish from a tank, there are a couple of rules to be aware of. The first is that removal should be immediate! Don’t wait for a second longer than you have to.

The second rule that you should follow is to use a net. Reaching into a fish tank with your bare hands is not a good idea. Your hands can introduce bacteria and diseases that aren’t good for your fish. When using a net, just make sure to sanitize it thoroughly afterward.

Outdoor Burial

One of the easiest methods of fish disposal is a burial. This is a great option for convenience and environmental benefits.

All you’ll need is a shovel and some dirt for this method. When burying a fish, dig at least 4 inches deep to avoid your fish becoming food for other animals.

Be sure to bury your fish, not in a zip lock bag or another container, as they aren’t biodegradable. Doing so will also allow your fish to function as a fertilizer to the soil it’s buried in!

This option is great for closure as you can bury your fish close to home and remember their grave as a flower bush or tree. You can even take solace in knowing that your fish is helping the environment.


Another option that is great for closure but is a bit more expensive is cremation. Cremation is a great way to have a piece of your pet with you forever.

If you decide to cremate a fish, you should never do it at home. This option is safest for a vet or even a pet cremation clinic!

Throw Your Fish Away

This method is a bit more controversial, but when done properly is still a moral way to dispose of a dead fish.

Throwing your fish away is a better option for those who aren’t as sentimental with their fish. To do this properly, you will need a biodegradable container to secure your fish. This protects the environment and the people who have to sort through your waste!

Plant Burial

Similar to the outdoor burial option, a plant burial may be better suited for those who don’t have their own yards or even those who just like plants.

This method involves burying your fish in a potted plant. As long as you bury your fish a minimum of 4 inches deep, you can avoid any unwanted smells or the spread of germs. Your plant will also be able to use the nutrients from your fish!


It will never be easy to euthanize a pet, but it will always be an important one. We hope that after reading this article, you’ll make the best decision for you! And even more so, we hope humanity is at the forefront of that decision!

After euthanizing a fish, make sure you also have the plan to dispose of them. Proper care is the best way that you can honor both your pet and the environment you inhabit.

Sharing is caring!

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.