What Your Axolotl’s Gills Are Telling You

Healthy axolotl gills are usually feathery, symmetrical, and gently fanned out from the head. Color varies by individual, morph, activity level, and blood flow, so some axolotls naturally look pinker or darker than others. Mild movement with breathing is normal, and occasional trips to the surface for air can also be normal because axolotls have lungs as well as gills.

What matters most is change. If your axolotl's gills suddenly look less full, more tightly curled, irritated, or uneven, compare that with its usual appearance. Taking weekly photos can help you spot gradual changes that are easy to miss day to day.

When the gill stalks are pulled forward toward the face, stress is high on the list of possibilities. In axolotls, one of the most common triggers is water current. VCA specifically notes that rapid or forceful water flow can cause stress and damage the external gills.

Forward curl does not tell you the exact cause by itself. Check whether the filter output is pushing the axolotl around, whether an air stone is creating too much turbulence, whether the tank was recently rearranged, or whether temperature and water chemistry changed. If the curl settles after you reduce flow and stabilize the environment, that supports a husbandry-related cause.

Gills that look shorter, thinner, or less feathery may suggest long-term stress, repeated irritation, prior injury, or poor water conditions. High ammonia, detectable nitrite, chlorine exposure, and chronic overheating can all injure delicate gill tissue in aquatic animals. Merck Veterinary Manual lists ammonia, nitrite, and chlorine among important water hazards, and recommends ammonia and nitrite at 0 mg/L in freshwater systems.

This kind of change is worth taking seriously even if your axolotl is still eating. Chronic gill changes can mean the setup needs adjustment, or that your axolotl needs a veterinary exam to look for infection, parasites, or other disease affecting the skin and gills.

Gill color can shift with activity, stress, temperature, and circulation. A temporary pinker look after feeding or movement may be normal. But persistently pale gills can raise concern for poor oxygenation, poor water quality, shock, or systemic illness. Very dark, inflamed, or blotchy areas may suggest irritation, tissue damage, or infection.

Because color is influenced by lighting and morph, use it alongside behavior. If color change comes with lethargy, surface gulping, poor appetite, or abnormal floating, contact your vet. Bring your recent water test values and a photo timeline if you can.

White or gray cottony material on the gills is often treated by pet parents as 'fungus,' but the appearance alone does not confirm the cause. It can reflect fungal overgrowth, secondary infection, or damaged tissue collecting debris. Warm water and poor water quality increase the risk of these problems in axolotls.

Because the gills are delicate and essential, visible fuzz is a good reason to see your vet promptly. Avoid guessing with over-the-counter aquarium medications, especially products not labeled for amphibians. Many fish medications are not safe or well studied for axolotls.

Write down the water temperature, ammonia, nitrite, nitrate, and whether tap water was dechlorinated. For freshwater aquatic systems, Merck lists ammonia and nitrite at 0 mg/L, nitrate ideally under 20 mg/L, chlorine at 0 mg/L, and dissolved oxygen above 5 mg/L. Also note whether the tank is cycled, how often water changes are done, and whether anything new was added.

Then look at husbandry details that commonly affect gills: strong filter flow, tankmates that may nip, recent heat spikes, missed maintenance, and substrate that traps waste. VCA notes that temperatures above 24°C (75°F) can make axolotls sluggish and more prone to infection, and that strong flow can damage gills. These details help your vet narrow the possibilities faster.

See your vet immediately if your axolotl has severe breathing effort, repeated frantic surfacing, uncontrolled floating, sudden collapse, major skin sloughing, or rapidly worsening gill damage. These signs can go along with dangerous water conditions, severe stress, or serious disease.

If your axolotl is stable but the gills changed over days to weeks, schedule a prompt visit rather than waiting for things to worsen. Early care often focuses on correcting the environment and identifying whether infection or tissue injury is also present.