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Freshwater Eel

Freshwater Eel

includes tire track and spiney eel species

Freshwater Eels have an excellent sense of smell but can't see very well. Eels have an elongated, snake-like body and vary in size and coloration. They open their jaws to allow water over their gills for breathing. Recommended for experienced aquarists.

Freshwater Eel

Freshwater Eel Facts

average adult size: 1 to 3 feet long, some species can grow longer
average life span: depends on species
diet: carnivore
minimum aquarium size: 20+ gallons depending on species
water temperature: 72 to 82°F


A well-balanced freshwater eel diet consists of:

  • Feed frozen, live, pelleted or freeze dried food.


Things to remember when feeding your freshwater eel:

  • Feed once a day, usually in the evening.
  • Some have teeth to crush their prey.
  • Some may refuse food and eat only every 2 to 3 weeks.


  • Keep in an appropriate size aquarium; a well-sealed aquarium lid is mandatory as eels can easily escape. Provide hiding places and plenty of room to swim.
  • Use of copper-based medications is toxic to eels.
  • Stable water quality and parameters are critical to the health of aquatic life. If you are unsure of your water quality, Petco provides free water testing.


  • Freshwater eels are usually sedentary.
  • They tend to be nocturnal (active at night) and live in holes or caves.
  • Can be aggressive and eat smaller tank mates.

Habitat Maintenance

Daily: check filter, water temperature and other equipment.
Weekly: check water quality at least once a week.
Monthly: change 10-25% of the total volume of water every 2 to 4 weeks, or as needed.


Do not house with small, slow-swimming species. May become aggressive in an overcrowded aquarium.


Signs of a healthy eel

  • Clear eyes
  • Healthy appetite
  • Even coloring

Avoid overcrowded conditions, which are a major cause of stress and disease. Maintain good water quality with regular water changes and adequate filtration.

Red Flags

  • loss of color or appetite
  • spots or fungus on body or mouth
  • cloudy eyes
  • listlessness
  • labored respirations
  • erratic swimming

Common Health Issues

Health Issue Symptoms or Causes Suggested Action
Health Issue Ich Symptoms or CausesWhite spots appear on body and fins; Eel rubs against hard objects or swims awkwardly. Rapid respirations. Suggested ActionQuarantine eel immediately; use a commercial ich remedy for at least two weeks.


Ask a store partner about Petco's selection of books on freshwater eels and the variety of private brand products available for the care and happiness of your new pet. All private brand products carry a 100% money-back guarantee.

Because all aquatic life are potential carriers of infectious diseases, such as Atypical Mycobacterium and Salmonella, always wash your hands before and after handling your aquatic life or habitat contents to help prevent the potential spread of disease.

Pregnant women, children under the age of 5, senior citizens and people with weakened immune systems should contact their physician before purchasing or caring for aquatic life and should consider not having aquatic life as a pet.

Go to for more information about aquatic life and disease.

This care sheet can cover the needs of other species.

Note:The information on this Care Sheet is not a substitute for veterinary care. If you need additional information, please refer to the sources on the following page or contact your veterinarian as appropriate.

Developed with and approved by a qualified veterinarian.