Axolotl Care Guide: What Do Axolotls Need?

Axolotls are fascinating aquatic pets, but their needs are quite different from those of most tropical aquarium fish. They prefer cool water, need excellent water quality and aren't particularly fond of strong currents.

If you're thinking about keeping an axolotl, getting the aquarium set up correctly from the beginning can make looking after one much easier.

What size tank does an axolotl need?

Axolotls spend most of their time on the bottom of the aquarium, so floor space is more important than simply looking at the tank's capacity in litres.

For a single adult axolotl, we'd recommend an aquarium with a base of around 90 cm × 40 cm or larger, with bigger generally being better. If you're keeping more than one axolotl, you'll need considerably more space.

Axolotls can grow to around 20–30 cm long, so the tiny youngster you bring home won't stay tiny for long!

A secure lid is also a good idea. Although axolotls aren't renowned for escaping, they can occasionally make surprisingly energetic movements towards the surface.

Keep the water cool

This is one of the biggest differences between keeping axolotls and keeping tropical fish.

Axolotls prefer cool water, ideally around 16–18°C. Prolonged temperatures above approximately 20°C can cause stress and increase the risk of health problems.

In most UK homes you won't need an aquarium heater. In fact, keeping the aquarium cool during hot summer weather can be the bigger challenge.

Position the tank away from radiators, direct sunlight and other sources of heat.

For reliable temperature control, an aquarium chiller is the best option. As well as cooling the water, a correctly sized chiller can maintain a much more stable temperature, helping to avoid large temperature fluctuations that can cause additional stress.

Aquarium fans can help in some situations, but their effectiveness depends heavily on room temperature and humidity, and they may only reduce the water temperature by a few degrees. For aquariums that regularly become too warm, a chiller provides much more dependable control.

An aquarium thermometer is an inexpensive but essential piece of equipment.

Water quality is extremely important

Like fish, axolotls produce waste that is broken down by beneficial bacteria living mainly within the aquarium filter.

This is why an axolotl aquarium should be fully cycled before the animal is introduced.

In a properly cycled aquarium:

• Ammonia should be 0 ppm
• Nitrite should be 0 ppm
• Nitrate should be kept as low as practical through regular water changes

A liquid aquarium test kit makes it much easier to monitor these levels.

Tap water should always be treated with a suitable water conditioner before it's added to the aquarium. This removes or neutralises chlorine and chloramine, which can harm aquatic animals and the beneficial bacteria in your filter.

When choosing a conditioner for an axolotl aquarium, avoid products containing aloe vera or similar slime-coat additives, as these can irritate axolotls. Products specifically suitable for axolotls, such as NT Labs AxoSafe, or conditioners such as Seachem Prime, are better choices.

If you're setting up a new aquarium, an axolotl start-up bundle containing water conditioner and beneficial filter bacteria can be a convenient way to get the essentials together.

Choosing a filter for an axolotl

Good filtration is essential, but axolotls generally don't appreciate a strong current.

The aim is therefore to provide effective biological and mechanical filtration without turning the aquarium into a washing machine.

Sponge filters are popular with axolotl keepers because they provide gentle filtration. Internal and external filters can also work very well, provided the flow can be controlled or diffused.

If your axolotl is constantly being pushed around by the current or appears to be avoiding part of the aquarium, the flow may be too strong.

What substrate should you use?

Substrate is an important consideration because axolotls often investigate their surroundings with their mouths and can accidentally swallow material while feeding.

Gravel and small stones should be avoided, as swallowed pieces can cause an intestinal blockage.

A good option for an adult axolotl is very fine aquarium sand. As well as creating a more natural-looking aquarium, sand gives the axolotl a surface it can grip while walking around the tank.

Avoid anything coarse, sharp, or small enough to be swallowed and cause an obstruction.

Give them somewhere to hide

Axolotls don't need bright aquarium lighting and will appreciate having somewhere darker to retreat.

Caves, tunnels, aquarium-safe wood and other suitable decorations can all provide hiding places. Just make sure there aren't any sharp edges that could damage their delicate skin or gills.

Live plants can also be used, although you'll need species capable of coping with cooler water and relatively low light.

What do axolotls eat?

Axolotls are carnivores.

Earthworms are commonly used as a staple food for adult axolotls, while suitable axolotl pellets and other appropriate foods can provide variety.

Young axolotls generally need feeding more frequently than adults. As they mature, feeding every two or three days is often sufficient, depending on the individual animal, its size and the food being offered.

Remove uneaten food promptly so that it doesn't decompose and affect the water quality.

Regular maintenance

Even with a good filter, an axolotl aquarium still needs routine maintenance.

Regular partial water changes help control nitrate and remove dissolved waste. How frequently you'll need to change the water depends on the aquarium size, stocking level and nitrate readings, but weekly testing and partial water changes are a good starting routine.

When carrying out maintenance:

• Treat replacement tap water with a suitable axolotl-safe water conditioner
• Try to match the temperature of the replacement water reasonably closely
• Remove uneaten food and visible waste
• Don't replace all your filter media at once
• Clean biological filter media gently in removed aquarium water rather than untreated tap water

That last point is particularly important. The bacteria living in the filter are what keep ammonia and nitrite under control, so you don't want to accidentally remove them during cleaning.

Can axolotls live with fish?

Generally, axolotls are best kept in an axolotl-only aquarium.

Small fish may become food, while larger or more inquisitive fish can nip at an axolotl's exposed gills.

Keeping multiple axolotls together can be possible if they're of a similar size and there's enough space, food and hiding places, but you'll need to watch for aggression and accidental nipping.

Common axolotl care mistakes

Many problems can be avoided by getting a few basics right from the start.

Some of the most common mistakes are:

• Keeping the water too warm
• Introducing an axolotl before the aquarium has cycled
• Using gravel or swallowable stones
• Providing excessive filter flow
• Allowing ammonia or nitrite to build up
• Using an unsuitable water conditioner
• Overfeeding and leaving uneaten food in the aquarium
• Keeping unsuitable fish alongside an axolotl

Getting the environment right is usually much easier than trying to correct problems afterwards.

The essentials

Successful axolotl keeping doesn't need to be complicated. Concentrate on the fundamentals: plenty of floor space, cool clean water, stable temperatures, gentle filtration, safe surroundings and an appropriate diet.

Set the aquarium up properly, test the water regularly and keep on top of routine maintenance, and you'll have tackled most of the important parts of axolotl care.

At CDL Aquatics, we stock a range of aquarium products suitable for setting up and maintaining an axolotl aquarium, including water treatments, filtration products, test kits and maintenance equipment.

You can browse our Axolotl Care collection to find everything in one place.