When To Consider Fish Euthanasia and How Vets Euthanize Fish

A fish’s quality of life, just as for any other pet, should always be considered to make sure they are living their best fishy lives. This means certain terminal health conditions, declining health, or severe trauma may result in a fish being euthanized if they are suffering.

Humane fish euthanasia requires oversight from a trained veterinarian to ensure the best care for your fish family members.

When To Euthanize a Fish

When considering euthanasia of a pet fish, your veterinarian will discuss the events that led to this point in the fish’s life and review all recent diagnoses and treatments.

Although a terminal condition may be present, there are a few key points to consider when deciding to euthanize a fish patient.

Socialization

Most fish are social animals and want to be around their friends and/or family.

For schooling fishes, such as goldfish, koi, and many tropical fish, a fish who isolates or hides from others in their school is a serious medical concern. If the ill fish is still swimming with their tank mates and interacting, that is a positive sign that they are not suffering and less likely to be a euthanasia candidate.

Appetite

Pet fish are very willing to eat when food is offered, especially once routines have been established.

A fish who isolates and refuses to eat is likely sick and may require euthanasia, as recovery isn’t possible without energy from food. However, if they’re still eating or behaving normally, consult your veterinarian for next steps.

A severe decline in health, viral outbreak, or trauma may lead to a quicker discussion about euthanasia.

Remember, dietary and feeding regimen changes may be required for a sick fish, such as for fish with buoyancy disorders or geriatric issues. If you have any concerns about the state of your pet fish and if euthanasia should be considered, contact your local fish veterinarian.

How Vets Euthanize a Fish Humanely

Fish euthanasia methods are outlined in the American Veterinary Medical Associations Euthanasia Guidelines. These guidelines provide veterinarians with approved methods for all species.

Prohibited methods for fish euthanasia include freezing and chlorine, such as exposure to tap water in a toilet.

In fish, depending on the size and species in question, there are a few methods available for humane pet fish euthanasia. Do not attempt to euthanize your fish at home—only qualified veterinarians should euthanize a pet fish.

Clove Oil Fish Euthanasia

Clove oil, or eugenol, is a common dental analgesic that can be used by veterinarians to sedate fish at lower doses. Clove oil works by altering the activity of the receptors in the fish brain, rendering them unconscious.

Clove oil dosage will vary depending on the species requiring euthanasia and can be directed by your veterinarian.

Here’s how a vet euthanizes a fish with clove oil:

• Your vet will shake the clove oil and add it to a small container of pond or tank water with just enough water to cover your fish.

• Your fish will be placed in the medicated water and covered with a towel.

• Your vet will bring the container to a dark, quiet place for 20–30 minutes. It is common for fish to respond to the strong smell of the clove oil when they are first introduced to the container, but this will pass quickly.

Sedation and Pithing or Exsanguination

Due to a lack of understanding about the mechanics of fish death, wherein the fish may still have a heartbeat but no brain function, a two-step method of euthanasia is typically recommended.

For most veterinarians performing fish euthanasia, these steps include:

• Administering an overdose of an anesthetic, rendering the fish unconscious

• Ensuring death through pithing (destroying the brain tissue) or exsanguination (bleeding the fish)

Pithing and exsanguination do not cause pain, as the fish has already been anesthetized.

If fish euthanasia occurs at the veterinary office, it is typical for the pet parents to be present for the sedation portion of euthanasia, but not for the secondary method. The fish will likely be taken to the procedure area of the veterinary clinic for this part.

Methods to ensure humane fish death can be alarming and unsettling for those unfamiliar with the procedure. After the secondary procedure, your fish’s body can be returned to you if you choose.

Bringing Home Your Fish’s Remains

Once euthanized, a pet fish parent has all the same options as other deceased pets, including bringing them home for a private burial or sending your fish off for cremation.

If desired, you can bury your fish on your private property. It is highly recommended to dig a hole deeper than 12 inches to deter scavengers. There are typically no environmental guidelines for pet fish disposal. Biodegradable coffins for fish are available if desired.

Your fish can alternatively be sent for cremation at a local veterinary crematorium. More information can be found through your veterinarian. Crematoriums typically have many options for ash containment or conversion into other memorials.