🐠Axolotl aquarium and care: the complete guide (cold water, feeding)

The axolotl is not a fish but a neotenic amphibian reaching 20 to 30 cm that lives exclusively in cool water, ideally between 15 and 20 °C. It requires a tank of at least 80 to 100 L per individual, with no harsh pump since it hates current, and a very fine sand substrate to avoid deadly gravel ingestion. In summer, keeping the water below 22 °C becomes the main challenge.

Profile : 20 to 30 cm as an adult, 80 to 100 L minimum per individual, cool water between 15 and 20 °C.

Species profile

Lifespan

10 to 15 years

Adult size

25 cm

Minimum tank

90 L

Water temperature

15 to 20 °C

pH

7 to 7.5

Temperament

A placid, curious neotenic amphibian, to be kept alone or among axolotls, never with fish that nip its gills.

Health watch

intestinal blockage from swallowing fine gravel · heat stress and infections above 22 °C

Legal status

Listed on CITES Appendix II (Annex B of EU Regulation 338/97): keeping captive-bred individuals is allowed, but keep proof of origin, an invoice or a transfer certificate.

🩺 This health information is general in nature and does not replace a consultation: at the slightest doubt about your animal’s condition, talk to your vet.

The axolotl aquarium: volume and setup

The axolotl (Ambystoma mexicanum) is not a fish but a neotenic amphibian, so its aquarium is planned differently. Allow 80 to 100 L minimum per adult, in a tank longer than it is tall — it walks on the bottom far more than it swims. Choose very fine sand (under 1 mm) or a bare bottom: any gravel that fits in its mouth can cause a fatal intestinal blockage. Provide wide, smooth hides (ceramic tunnels, sanded terracotta pots), cool-water plants such as elodea and dim lighting, since bright light stresses it. Filtration stays gentle, with the output diffused by a spray bar: it hates current. Our axolotl habitat page and the guide to setting up an axolotl cold-water tank detail the equipment item by item.

Cold water and parameters: the 22 °C rule

This is THE point that sets the axolotl apart from almost every other aquarium inhabitant: it lives in cold water, ideally between 15 and 20 °C, and must never stay above 22 °C for long — beyond that, heat stress and infections set in quickly. No heater, then; the real challenge is summer, when an aquarium cooling fan or a chiller becomes necessary. The tank must be fully cycled before the animal arrives (allow three to six weeks): ammonia and nitrite at zero, nitrate kept low with a 20 percent weekly water change, pH between 7.0 and 7.5. Our guide to axolotl water parameters lists the values to test and what to do when they drift.

Feeding: what does an axolotl eat?

A strict carnivore, the axolotl eats dedicated sinking axolotl pellets, earthworms and bloodworms, offered with feeding tongs so you can check it actually eats. A juvenile feeds daily or almost; an adult only needs two to three meals a week. Never goldfish pellets, and never prey collected from treated ground. Portion details are on the axolotl food page.

Tank mates and handling

The axolotl lives alone or with same-sized axolotls: fish nip its external gills or end up swallowed, and two axolotls of different sizes maim each other. As for handling, it stays the exception: its permeable, scaleless skin tolerates neither dry hands nor whatever products they carry. Move it with a soft net or wet hands, as explained in our guide can you hold an axolotl?

Health and legal status

Gills curled forward, refusal to eat, uncontrolled floating or peeling skin all signal a problem — almost always water-related (temperature, nitrite) before being a disease. Never use salt or fish medication on its fragile skin; when in doubt, an exotics veterinarian experienced with aquatic animals is the only reference. Legally, the species is listed on CITES Appendix II (Annex B of EU Regulation 338/97): keeping captive-bred individuals is allowed, but keep the invoice or transfer certificate as proof of origin.

Common mistakes with a first axolotl

• Gravel: any swallowable substrate ends up ingested, blockage included — very fine sand or a bare bottom, no exceptions.
• Summer heat: a tank that hits 24 °C in July kills slowly; plan a fan or chiller ahead.
• An uncycled tank: nitrite spikes burn its gills long before anything is visible.
• Tank mates: fish, shrimp or a smaller axolotl — they all end badly.
• Repeated handling: this is an animal to watch, not to touch.

Frequently asked questions

What water temperature does an axolotl need?

Between 15 and 20 °C, never staying above 22 °C for long. No heater is needed — it should actually be avoided. The real challenge is summer: an aquarium fan, a cool room or a chiller depending on your climate.

Can you keep fish with an axolotl?

No. Fish nip its external gills, and anything that fits in its mouth ends up swallowed, gravel included. An axolotl is kept alone or with axolotls of strictly the same size.

How long does an axolotl live?

10 to 15 years in captivity, sometimes more, provided the water stays cold and clean year round. Most early deaths come from an uncycled tank, an overheated summer or swallowed gravel.

Axolotl gear, family by family

• 🍖 Food

  A carnivore: dedicated sinking axolotl pellets, earthworms and bloodworms, offered with feeding tongs. Adults need only two to three meals a week; never goldfish pellets.

• 🧴 Care & grooming

  Water must stay below 22 °C at all times: above that, stress and infections set in quickly. Gentle filtration, 20 percent weekly changes and no salt or fish medication on its fragile skin.

• 🎾 Toys & enrichment

  Wide, smooth hides such as ceramic tunnels, sanded terracotta pots and cool-water plants like elodea. Bright light stresses it: keep lighting dim or provide permanent shaded zones.

• 🏠 Bedding & habitat

  A tank of at least 80 to 100 L per adult, long rather than tall, with fine sand or a bare bottom and the filter output diffused by a spray bar. No cohabitation with fish, which nip its gills or end up swallowed.

• 🧳 Travel & safety

  Transport it alone in a rigid box half filled with its own tank water, kept cool with an ice pack shielded from direct contact. Handle it as little as possible, always with wet hands or a soft net.

• 🧰 Accessories

  An aquarium cooling fan or chiller for summer, an accurate thermometer, fine sand and feeding tongs. The chiller is the main expense, from 150 to 400 euros depending on the model.

Guides to read

• Community aquarium or species-only tank: which is right for a first setup?Bedding & habitat

  Community aquarium or species-only tank: pros, cohabitation risks and advice for choosing how to set up your first aquarium.

• Best easy aquarium plants without CO2 for beginnersToys & enrichment

  Which aquarium plants can you choose without CO2 injection? A selection of hardy, easy plants for a beginner's planted tank.

• Budget for a first brackish water aquarium: the real cost to get startedBedding & habitat

  How much does a first brackish water aquarium cost? Tank, filtration, salt and salinity monitoring, budgeted item by item.

• Changing filter media too often: the mistake that wrecks your aquarium's cycleCare & grooming

  Why you should never replace all your filter media at once: nitrifying bacteria, replacement frequency and the right habits.

• Restarting a neglected aquarium: a step-by-step guideCare & grooming

  How do you restart an aquarium that's been left neglected without endangering the fish? Steps, water changes and mistakes to avoid.

• GH, KH and pH: understanding and adjusting aquarium water hardnessCare & grooming

  GH, KH, pH: what do these three readings actually measure, and how do you adjust aquarium water hardness without stressing the fish?

• Upgrading to a bigger aquarium: moving your fish without the stressBedding & habitat

  How do you upgrade to a bigger aquarium without breaking the biological cycle or stressing your fish? Steps and mistakes to avoid.

• Aquarium electrical safety: GFCI protection and good habitsTravel & safety

  Heater, filter, lighting near the water: what electrical precautions keep an aquarium safe for fish and people?