Axolotl Ambystoma mexicanum
A salamander that stays in its larval form for life and can regrow entire limbs. It looks like an ornamental fish but it is the most temperature-sensitive amphibian in the hobby — problems start above 24 °C, and that single threshold is the whole difficulty.
⚖️ Legal status · Check the source
Wild populations survive only in Lake Xochimilco, Mexico and are critically endangered; the species is listed on CITES Appendix II. Pet-trade animals are long-established captive-bred strains and are commonly kept. Confirm captive-bred provenance and keep your receipt; because this is an Appendix II species, verify the specific requirements with your local wildlife authority. Never release it.
Check another species →Key parameters
- Lifespan
- 10-15 years
- Adult size
- 23-30 cm total length
- Diet
- Carnivorous. Earthworms are the ideal staple, supplemented with bloodworms and sinking axolotl pellets. Never feed live feeder fish
- Temperature
- 16-18 °C is ideal, sustained above 22 °C is harmful, and above 24 °C is life-threatening
- Humidity
- Fully aquatic — what matters is water temperature and quality, not air humidity. The tank must be fully cycled with ammonia and nitrite at zero
✅ Suits you if
Anyone who can hold water below 20 °C year-round, is willing to maintain a cycled filter, and enjoys an aquarium display animal
🚫 Do not get one if
Hot summer rooms with no plan for chilling; anyone wanting an animal they can handle — axolotl skin is extremely delicate
Starter equipment list
Buy all of it before the animal arrives, not after.
- Tank: 75 L (20 gallons) minimum for one adult. Footprint matters more than depth; 25-30 cm of water is plenty
- A cooling plan — a chiller, a fan unit, or an air-conditioned room. One of the three is mandatory, and it is the item you must not economise on
- Substrate: bare bottom or fine sand. Never gravel — impaction from swallowed gravel is the second biggest killer after heat
- Filtration: low flow. Axolotls are still-water animals and strong current causes constant stress
- Hides: terracotta pots or PVC pipe, with no rough or sharp edges
- Water conditioner and a test kit. The tank must be fully cycled before the animal goes in
Most common beginner mistakes
- 1 Losing control of the water temperature — no summer cooling plan is the most common cause of death. An axolotl will not survive a 30 °C room
- 2 Gravel substrate — an axolotl inhales everything around its food, so gravel gets swallowed and causes impaction. Bare bottom or fine sand only
- 3 Feeder fish — they carry parasites, and some species contain thiaminase which causes vitamin B1 deficiency. Earthworms are the correct staple
- 4 Housing with fish — fish nip at the gills, and the axolotl swallows small fish. Both sides lose
- 5 Co-housing juveniles — they bite each other's limbs off. The limbs regrow, but there is no reason to put them through it
- 6 Handling — an axolotl is almost unsupported by bone and absorbs substances directly through the skin. Do not lift it out of water unless necessary
Common illnesses
| Illness | Common cause | What you'll see |
|---|---|---|
| Heat stress | Water above 22-24 °C — the leading cause of death | Gills shrinking and paling, hanging at the surface gulping, refusing food, skin shedding slime |
| Impaction | Swallowing gravel substrate | Distended abdomen, no defecation, refusing food, hind-limb weakness |
| Fungal infection (Saprolegnia) | Deteriorating water quality, or fungus taking hold on an injury | Cotton-wool-like white growth on the body or gills |
| Ammonia poisoning | An uncycled tank or a failed filter | Reddened gills, red patches on the skin, frantic swimming or unnatural stillness |
| Bloating / floating | Water too warm, digestive problems, swallowed air | Tipping sideways or unable to sink, floating at the surface for long periods |
Frequently asked
Do the limbs really grow back?
Yes, complete with bone, muscle and nerve — it is what axolotls are famous for. But regeneration costs a great deal of energy and the wound can become infected, so prevent the injury rather than relying on the repair.
How do I cool the tank in summer?
In order of reliability: air-conditioning the whole room is the most stable, an aquarium chiller is precise but expensive, and a clip-on cooling fan is cheapest but limited and accelerates evaporation. Whichever you choose, install and test it before summer arrives.
How can I tell if it's healthy?
Look at the gills. A healthy axolotl has full, feathery gills in bright red or pink. Gills that shrink, pale, or fold forward against the head are the early warning that water quality or temperature has gone wrong.