Regrettably, dealing with fish death is an inevitable part of maintaining aquariums, and it never gets any easier. However, being aware of the correct steps to take when a fish dies can act as a safeguard, potentially preventing your other fish from suffering the same fate. Adhering to best practices is undoubtedly advantageous for both us and our environment.
Article Summary
- Proper disposal of a dead fish is important to prevent harm to other fish and the environment.
- Flushing a dead fish down the toilet is discouraged, as it can harm the environment and local wildlife.
- Proper disposal methods help avoid ammonia spikes, keep other fish safe, and show respect for the deceased pet.
The death of a fish can be pretty overwhelming and it’s easy to get overloaded with what you need to do as there is a plethora of information available.
If you’re not sure how to dispose of dead fish, you’re in the right place. I’ll be going over the best (and safest) ways to remove deceased fish. Read on to find what I believe to be the best practices to follow.
What Do You Do When a Fish Dies in Your Tank?
When a fish dies in your tank, the first thing you need to do is remove it…
When a fish dies in your tank, the first thing you need to do is remove it. However, make sure it’s definitely dead beforehand as they could be sleeping, playing dead (species of catfish and clown loaches are notorious for this!), or simply not moving at that time.
Dead fish can sink or float, but small fish like guppies and neon tetras will usually float. Use a net to gently lift your pet and take it out of the water.
Signs of Life
Most alive aquarium fish will squirm or start thrashing once they are removed from the water.
If your pet doesn’t do this, check for other signs that they could be alive like gill and eye movement. The last thing to do is feel the body. If it feels rigid or stiff, your pet has most likely passed away.
How to Dispose of Dead Fish
After you’ve checked your pet fish over and made certain that they are no longer alive, you’ll now need to correctly dispose of it. I’ll be explaining how to safely dispose of a dead fish below to help you get through the process a little easiest.
Take the Dead Fish Out of Your Aquarium Right Away
While it’s an unpleasant job and something every aquarist dreads to see, a dead fish should be removed from the aquarium as soon as possible.
The decomposition process happens quickly in dead fish, especially in warm water, which can emit a pungent odor if the body is left.
Avoid Harming Your Other Fish
Dead fish can cause ammonia spikes, which could lead to your tank crashing and harming your live fish. In addition, the dead fish could have been suffering from a contagious illness or disease that could cause other fishes in the aquarium to fall ill, particularly if they attempt to eat the dead fish.
TIP
Use a net to remove the body rather than your hands to limit the spread of germs and bacteria. Clean the net in hot water or in a 10% bleach solution by combining 9 parts water with 1 parts bleach. Rinse the net thoroughly under water and allow it to air dry.
How Long Can You Leave a Dead Fish in Water?

A dead fish can wreak havoc in your aquarium, especially if it’s on the larger side and left in your tank for more than a couple of hours.
Within that time, the deceased fish will begin to leach ammonia and other toxic compounds into the water and may become a tempting snack to other residents in your tank.
Put the Fish in a Ziploc Bag
After you’ve removed the fish, place it into a ziploc bag or paper bag and seal it securely to prevent any bad smells. If you can’t dispose of your pet just yet, put the plastic bag in an airtight container like an empty ice cream tub and put it in your freezer to slow down the decomposition process.
Dispose of the Dead Fish
After you’ve removed your dead fish from your aquarium and bagged it up, you’ll need to decide on a disposal method.
You can either bury the fish’s body, put it in your waste disposal, or cremate it. Most fish owners bury their pet, but how you dispose of your dead fish is down to personal preference.
Burying
Burying your fish is a good way of giving it a second purpose, allowing it to become a food source for plants.
Deceased fish contain nitrogen and trace amounts of other minerals, so the nutrients released as it decomposes can help fertilize plants.
Bury It in your Backyard
If you have a backyard, choose a burial location for your fish such as under flowers, bushes, or a tree. Using a shovel or hand trowel, dig a hole.
Place the fish in a paper bag or a container made from biodegradable material like a cardboard box instead of a plastic bag as it’s more environmentally-friendly.
Put the bagged fish into the hole you’ve just dug and cover it with soil. Pay tribute to your beloved fish by adding some flowers, rocks, or sticks to the site.
TIP
You could create homemade grave markers like a wooden sign to serve as a nice reminder of your fish whenever you or your family members step into the backyard
Bury it in a Potted Plant

Alternatively, you can bury the fish in a potted plant. Again, deceased fish are high in nitrogen, so they’re beneficial for new plant growth and a great natural fertilizer.
Choose a large pot and place the dead fish inside, then cover it with some soil and add your plant. Ideally, opt for an outdoor plant as, otherwise, the decomposing fish body could stink up your home.
How Deep Should I Bury My fish?
When burying your fish outside, dig a hole that’s at least 4 to 5 inches deep to prevent any domestic or wild animals from digging it up. Some aquarists add a layer of kitty litter to the burial site to mask the smell.
TIP
Putting a paving slab or large rock on top is also a great idea as it discourages animals from digging up the dead fish.
Put the Body in Your Waste Disposal
If you don’t have access to a backyard/outdoor space or don’t fancy burying your fish, you can put your fish in the trash. Wrap your fish in a paper bag or another biodegradable material, then put it in a cardboard box.
Not only will this reduce the smell, but it will prevent sanitation workers from touching your dead fish. After you’ve placed the bagged fish into a biodegradable box, put the fish in the trash outside.
Cremate the Dead Fish
If you don’t want to bury your deceased pet fish or put it in the trash, another good disposal method is cremation. However, this should never be attempted by yourself at home unless you know what you’re doing.
Safely cremating a fish requires experience and the proper equipment, otherwise, you could injure yourself.
Speak to your vet or contact a local pet crematorium if you’re interested in getting your dead pet cremated.
If you think you can safely cremate your pet yourself, dry them out thoroughly first by putting them on a cookie sheet covered with aluminum foil in an oven heated between 392 to 482 degrees Fahrenheit.
Cremation Process
Leave them in the oven for at least 15 minutes or however long it takes your fish to completely dry out. Let them cool for a few hours, then build a fire in a fire pit or other fireproof container. Wait for the embers to get hot.
Get an old ceramic plant pot and put your pet inside, then place it on top of the fire. Once the ashes are the right texture you desire, leave them to cool and collect them. You can either scatter your fish’s ashes or put them inside a container or locket.
Is It OK to Flush a Dead Fish Down the Toilet?
Although most people opt to flush their dead fish down the toilet, this is actually the worst way to dispose of a fish. It may be the quickest and easiest method, but it’s extremely harmful to the environment and local wildlife.
Besides, it’s not exactly the kindest disposal method of a beloved pet. Burying or cremating fish is far more thoughtful, but even putting your fish in the trash is safer than flushing them down the toilet.
Learn more about its negative impact in the video below
Impact of Improper Disposal of Fish
If you don’t dispose of a dead fish properly, it can have drastic consequences on the environment or your tank if you don’t remove it. Leaving a deceased fish in an aquarium can result in ammonia spikes, which could kill other animals in your tank.
Alternatively, if you don’t bury your pet in a deep enough hole, it’s likely to smell or be dug up by animals like cats and racoons.
Worst of all, flushing a dead animal can be extremely harmful to local waterways, wildlife, and native fish species, especially as some sewage drains lead to rivers and oceans. When fish die, never flush them down the toilet or other drains – bury, cremate, or put them in the trash.
Why You Should Never Flush Your Dead Fish Down the Drain
You should never flush your pet dead fish down the drain as it can have serious consequences on local wildlife and waterways. Once a fish has been flushed, it will enter the main sewage system.
Not all sewage drains connect to a septic plant – some go straight to oceans and rivers. This means your dead fish could end up in a new ecosystem with wild species.
The immune systems of wild fish species are not equipped to deal with illnesses and diseases found in captive fish, including parasitic infections and ich.
If a native fish contracts an illness or disease from a captive-bred fish, it has the potential to wipe out wild fish populations and destroy an entire ecosystem.
Things to Do After Disposing Dead Fish
Once you’ve disposed of a dead fish, it’s a good idea to figure out the cause of death so you can prevent your other fish from meeting the same fate.
While a newly acquired fish is susceptible to dying because of stress from delivery or during transit, it is still best to check your other fish over for signs of illness/disease, such as sores/white spots on the body, listless or lethargic behavior, rapid breathing and gill movement, gasping for air at the surface of the tank, and erratic swimming.
Test your aquarium water for ammonia and nitrite to make sure the dead fish didn’t release any toxic compounds into your fish tank water. If the water parameters are incorrect, it may cause your other fish to leap out of the water.
If it’s been over 24 hours since your last water change or you’ve found ammonia/nitrite in your tank, perform a 25% water change to lower the ammonia level in your tank.
Check your ammonia/nitrite levels in a few hours to see if they’ve dropped, then again the next day. You can also add a probiotic bacteria supplement to eradicate any bad bacteria lingering in your tank.
RECOMMENDATION
For some extra peace of mind, add a water conditioner that neutralizes ammonia such as Seachem Prime. It detoxifies ammonia and nitrites for 24 hours, so it’s a good option if you’re currently struggling with high levels of both these compounds.
Final Thoughts
Although losing a pet fish is hard, giving them a proper burial allows you to pay homage to your fish’s life and help you and your family make peace with their death. But if cremation or burying aren’t suitable options, you can still dispose of dead fish safely in the trash.
Remember, the worst way to dispose of a dead fish is by flushing it down the toilet or drain as it can harm wildlife and the environment.
Feel Free To Share!
I hope I helped you learn how to dispose of dead fish and what you need to do if your fish dies. If you know any other fish lovers or pet owners, be sure to share this guide around.
Feel free to check out my other fish care guides if you need some more advice or tips!