Can Axolotls Have Tank Mates?

A golden albino axolotl with a leucistic axolotl tank mate. Photo credit: Meghan Saylors.

Introduction

Many keepers look into their axolotl's spacious tank and feel that something is missing. A school of fish? A plecostomus or two? An escargatoire of snails? Are there any tank mates that are truly safe for your axolotl to cohabitate with? Sadly, the answer is... not really. Read on to find out why.

An axolotl that attempted to swallow a catfish, resulting in the death of the fish and injuries sustained by the axolotl.

Fish Tank Mates

Most fish will pick at an axolotl's gills and cause injury. Those fluffy, feathery appendages just look appetizing! Fish will mistake them for small worms and try to tear them off, causing stress and injury to the axolotl.

Most fish can also fall victim to the axolotl's voracious appetite. Fish are not a safe or suitable food for axolotls, due to their difficult to digest bones and the thiaminase content found in some of their bodies. Long-term consumption of this thiaminase can result in vitamin B deficiency for the axolotl.

Despite some fish being labeled as "feeder" fish, they can actually easily transmit diseases and parasites to your axolotl, along with the vitamin deficiencies from consuming their thiaminase. Fish are not quarantined properly by pet stores or treated for pathogens and parasites. We do not recommend feeding fish or shrimp to your axolotl without first quarantining and monitoring the animals for illness for at least 30 days.

Many tropical fish require warmer temperatures than an axolotl's ideal range of 15-20˚C (60-68˚F), which is just another reason why the two are not compatible.

An axolotl whose slime coat was eaten by a plecostomus fish.

Plecostomus Tank Mates

While many keepers add a plecostomus, or suckerfish, to their tank in an effort to combat algae buildup, it should be noted that many pleco species quickly outgrow their desire to eat algae and move on to a protein-based diet. They will latch onto the axolotl in an attempt to eat its skin and slime coat, which can result in fatal wounds, like the ones shown here.

Many plecostomus species grow to be very large, and need more space than the typical axolotl tank can offer. There are even reports of plecostomus attacking other animals to defend their territory.

Plecostomus have barbed spines that can cause injury if they are swallowed by an axolotl. It would be nearly impossible to remove a stuck pleco from an axolotl's mouth.

Most plecostomus species require warm water in the range of 22–30°C (72–86°F). Axolotls require cool water in the range of 15-20˚C (60-68˚F). Forcing one to live in the other's ideal environment would result in constant stress for the animal.

Here are some examples of axolotls that have been injured either by swallowing fish, having their gills picked at, or their slime coat attacked by a plecostomus.

An axolotl whose slime coat is being eaten by snails. The axolotl is also housed on gravel, which is a dangerous substrate for axolotls. Source: @ambystoma_den.

Snail Tank Mates

Snails have been known in many cases to suction onto your axolotl in an attempt to feed off their slime coat. The axolotl uses its slime coat as a first defense against disease and infection.

There are reports of axolotls swallowing snails and becoming impacted on the shell, which cannot be digested. There are even documented cases of axolotls who cut their mouths on a mystery snail's sharp trapdoor. Here are some examples of axolotls that have been injured by snails.

An axolotl that attempted to eat a snail, but was unable to swallow nor spit it out, resulting in needing manual removal with tweezers. The axolotl was injured with a swollen mouth for some days, but eventually began eating again and returned to normal.

Other Axolotls as Tank Mates

While many keepers house axolotls of the same sex and size together successfully, cohabitation does not come without risk.

Axolotls create large amounts of waste, which result in large concentrations of nitrate. To dilute the axolotl's excessive bioload and to prevent stress on the inhabitants, two axolotls should be housed in no less than a 227 liter (60 gallon) tank, while a 283 liter (75 gallon) tank is preferred. We recommend a minimum of at least 113 liters (30 gallons) per axolotl.

Axolotls have been known to mistake one another's limbs, gills, and tails for food, resulting in traumatic injury like the ones shown here. Their bite is strong enough to break their tank mate's bones, rip tails off, and even amputate limbs. This is especially likely if the axolotls are close by each other during feeding time, or if they are not fed frequently enough.

Wild type axolotl with a cherry shrimp tank mateon top of a Marimo moss ball. Credit: Silvia Ochoa.

Safe Tank Mates: Shrimp

Wait... we said that there weren't any safe tank mates! So what's all this about shrimp?

Freshwater shrimp, such as ghost or cherry shrimp, are perfectly safe for your axolotl to snack on. They won't hurt the axolotl, and they even clean up a small amounts of algae and leftover food. The downside is that axolotls see them as a tasty treat, so they don't often last very long.

Because shrimp can potentially carry parasites and diseases, as with any other new tank mate, they should be quarantined in a separate holding area to monitor for diseases for a minimum of 30 days before introducing them to your axolotl.

Conclusion

Axolotls are always the safest when kept solitary. Axolotls are not social animals, so there is no need to worry about their loneliness! The only tank mates that can really be kept with axolotls without any risk of injury, impaction, or choking are small shrimp.

Even other axolotls have a high risk of injuring each other, even accidentally, due to their poor eyesight and ambush predator instincts. Injuries from other axolotls especially can be very severe and require treatment. We hope that this article can help make others aware of all the associated risks with keeping each type of tank mate with an axolotl.