Axolotl Care Guide: Tank Setup, Temperature, Water and Feeding

Axolotls (Ambystoma mexicanum) are among the most fascinating pets you can keep. These Mexican salamanders stay in their aquatic, larval form all their lives, complete with feathery external gills and a permanent smile. They're also hardy and personable, and can live 10–15 years. But they have very different needs from tropical fish, and most problems come from keeping them too warm.

Axolotl care at a glance

Choosing the tank

Adult axolotls reach 20–30cm, and they spend most of their time on the bottom, so floor space matters more than height. A standard 90cm aquarium is ideal for one or two adults. A secure lid is important, as axolotls occasionally jump. Keep the tank away from radiators, windows and direct sunlight.

Keeping the water cool

This is the most important part of axolotl care. Axolotls are coldwater animals: no heater is needed. Above about 22°C they become stressed, stop eating and are more prone to fungal infections. In a UK home, the challenge is summer.

• Monitor the temperature daily with a digital thermometer such as the Fluval 2-in-1 Digital Thermometer.
• Fit a clip-on cooling fan for warm spells. Fans cool the water by evaporation and can lower temperature by a few degrees. The TMC Aquarium Cooling Fan, combined with the TMC Cooling Fan Thermostat Controller, switches on only when needed. The Aqua Medic Arctic Breeze is another good option.
• In very warm rooms, a chiller may be needed. See our chillers and cooling range, and our guide to keeping your aquarium cool in hot weather.
• Use LED lighting, which produces little heat, and keep the light period short. Axolotls have no eyelids and prefer dim conditions.

Substrate: sand or nothing

Axolotls feed by sucking in food, and they often swallow whatever is around it. Gravel and small pebbles can cause fatal blockages. Use either:

• Fine sand that passes through the gut safely, such as Hugo Kamishi Natural Aquarium Sand. Rinse it well before use.
• A bare bottom, which is easiest to clean, although some axolotls find it hard to grip.
• Large, smooth stones bigger than the axolotl's head can be used as decoration.

Browse our freshwater substrates.

Filtration and flow

Axolotls produce a lot of waste and need good biological filtration. But they come from still lake water, and strong currents stress them; you may see gills curling forward. Choose a gentle filter, or baffle the outlet with a sponge or spray bar. Sponge filters and adjustable internal filters work well. See our internal filters. Make sure the tank is fully cycled before adding axolotls; our guide on how to cycle an aquarium explains how.

Water quality

• Test weekly for ammonia, nitrite and nitrate. Ammonia and nitrite should always be zero, and nitrate below 20–40 ppm.
• Change 20–30% of the water each week, with dechlorinated, temperature-matched water.
• Seachem make products specifically for axolotls. Seachem Axolotl Conditioner removes chlorine and chloramine, and Seachem Axolotl Buffer keeps pH and hardness at the right level.
• Avoid aquarium salt and most fish medicines unless a vet advises them. Axolotls are very sensitive to chemicals.

Decor and hides

Axolotls like somewhere dark to retreat to. Smooth caves, large pieces of wood and hardy plants such as java fern and anubias all work well; read our guide to easy aquarium plants. Avoid anything sharp or with small holes an axolotl could get stuck in, and make sure decor is stable.

Feeding

Axolotls are carnivores. Juveniles eat daily; adults every two to three days.

• Staple: earthworms are the best all-round food. Quality sinking pellets designed for axolotls or carnivorous fish are a convenient alternative.
• Treats: frozen bloodworm such as Gamma Bloodworm is popular, especially with juveniles, but isn't nutritious enough as an adult staple. See our frozen foods.
• Remove uneaten food after about 15 minutes, using feeding tongs to target-feed if needed.

Tankmates

Axolotls are best kept alone or with other axolotls of a similar size. Fish nibble their gills, and many axolotls will try to eat anything small enough to fit in their mouths. Very young axolotls can nip each other's limbs, which usually grow back.

Common health problems

• Curled-forward gills: a sign of stress, usually from strong flow or poor water quality.
• Floating: often trapped air from gulping at the surface, and normally harmless. If it persists, check temperature and diet.
• White, fluffy patches: fungus, often linked to warm water. Cool the tank and seek advice.
• Not eating: check the temperature first.

Buying an axolotl

Set up and cycle the tank before buying. We stock captive-bred axolotls in several colours, including Leucistic Pink, Albino Golden and Wild Coloured. Browse our Fish Shop, and ask our team if you'd like help choosing equipment.