Why Is My Axolotl Biting the Other Axolotl?

Abdul Wasay Khatri | Administrator

Last updated: 9 January, 2026

Direct Answer

Your axolotl is biting the other one because of food competition, size differences, cramped tank space, or mistaking body parts for food. Axolotls have poor eyesight and use their sense of smell to hunt, which means they sometimes bite each other’s gills, tails, or limbs by accident. Separate them immediately if the biting causes injuries or happens repeatedly.

Common Reasons for Biting Behavior

Axolotls bite each other most often during feeding time. When you drop food into the tank, both axolotls rush toward it and may accidentally bite each other in the frenzy. Their gills and toes look similar to worms, which triggers their feeding response. This gets worse if you’re not feeding them enough or if one axolotl is more aggressive about food.

Size matters a lot when keeping multiple axolotls together. If one is significantly bigger than the other, it may see the smaller one as prey. A good rule: don’t house axolotls together if one’s head is bigger than the other’s body. The size gap makes biting more likely and more dangerous.

Tank size plays a big role too. Two axolotls need at least 30-40 gallons of space. In smaller tanks, they bump into each other more often, leading to stress and territorial behavior. Stress makes axolotls more aggressive, and they may bite to establish dominance or defend their space.

What to Do About the Biting

Check both axolotls for injuries first. Look for missing toes, damaged gills, or bite marks on the body. Minor injuries usually heal on their own thanks to their regeneration abilities, but deep wounds need immediate separation to prevent infection. If you see blood or white fuzzy growth (fungus), move them to separate tanks right away.

Feed them in different corners of the tank or use a turkey baster to target-feed each one individually. This reduces competition and prevents feeding frenzies. Some owners feed their axolotls in separate containers entirely, which works well but takes more time. Make sure each axolotl is getting enough food underfed axolotls are more likely to bite each other.

Watch their behavior over the next few days. Occasional nipping during feeding is normal, but constant harassment means they can’t live together. Some axolotls just don’t get along, and that’s fine. It’s better to house them separately than risk serious injuries. You’ll need a second tank setup if separation becomes necessary.

FAQ

Will my axolotl’s bitten gill grow back?
Yes, axolotls can regrow gills, toes, and even limbs. Keep the water clean and the injured axolotl will regenerate the missing parts in 4-8 weeks. Watch for signs of infection during healing.

Should I separate them permanently?
Separate them if biting happens daily, causes visible injuries, or one axolotl is clearly stressed. Some pairs live together peacefully, others don’t. There’s no shame in housing them separately.

Can I keep three axolotls together to reduce aggression?
No, adding more axolotls usually makes things worse. You’d need 50+ gallons and perfect water conditions. Pairs are hard enough avoid groups unless you’re an experienced keeper with a massive tank.

Is the biting axolotl being mean or just hungry?
Neither. Axolotls don’t have complex emotions. They bite because of instinct, poor vision, or stress. Don’t blame the “aggressive” one fix the environment instead.

My axolotls were fine for months, why start biting now?
Changes in tank conditions, one growing faster than the other, or seasonal breeding behavior can trigger biting. Check water parameters and compare their sizes again.

Abdul Wasay Khatri
Administrator
Abdul Wasay is the founder and lead author of Axolotl Portal, a trusted site for axolotl care. He spent almost nine months learning about axolotls, including their tanks, feeding, water care, and common health problems. His knowledge comes from trusted vets, research, and real experience from long term axolotl owners. All Posts by