Unhealthy axolotl gills often appear pale or white, tightly curled forward (indicating stress from poor water quality), small with few filaments, or covered in white, fuzzy patches (fungus/Columnaris). Healthy gills are vibrant pink/red, fluffy, and feathery, with full filaments, while signs of illness include shrinkage, paleness, or raggedness.
To make sure your Axolotl as healthy you want to check how fluffy the gills are, rather than how long they are because length is determined by genetics but the fluff on the gills is determined by water quality and health.
Health issues found in axolotls such as fungus, lack of appetite, curled gills, bacterial infections, and more need to be treated as soon as possible. If your axolotl is showing signs of stress or illness, the most common reason is that there is something wrong with their aquarium environment.
The Gills of an Axolotl
De axolotl distinguished by feather-like external gills on either side of its head. These gills not only provide its distinctive appearance but also serve as important respiratory organs.
A lot of people confuse fungus and Columnaris on axolotls. True fungus (Saprolegnia) looks like white, cottony tufts and usually comes from poor water quality, stress, or injury. Columnaris is actually a bacterial infection but looks similar — slimy, gray-white fuzzy patches on gills, often mistaken for fungus.
Resist the temptation to pull the fungus off. It is painful and will cause further damage. There are treatments but be aware that many fish medications are toxic to axolotls. Safe treatments for axolotls include Methylene Blue, Potassium Permanganate & Fritz Maracyn Oxy.
Ensure proper airflow in your axolotl's tank by using a sponge filter or air stone. Light water movement promotes oxygen-rich water, which helps maintain big, beautiful gill filaments—an iconic trait of healthy axolotls!
Axolotl gills are usually a vibrant pink or red, depending on pigmentation and blood flow. When they start to turn white or pale, especially the stalks, it's often a sign that something is off in the tank environment, particularly with water quality.
This stunted body can be caused by malnutrition and poor living conditions. “Dwarf” axolotls have stunted, disproportional bodies. They can often be identified at a young age by their short, round torso and curvy tail.
The structure of the gill
The deep red colour of the normal gill filament is a reassuring sight to Koi-keepers as this is a good indication that the gill is healthy. The filaments are comprised of what are termed the primary and secondary lamellae and there are two paired filaments in each gill cavity.
Signs to look out for in a stressed or unhealthy axolotl may be curled gills, hooked tail tip, small gills, sparse filaments, red spots, etc.
When axolotls are not active, swimming or feeding, they tend to hide and relax, because they don't have eyelids, sometimes if they are not moving they are simply sleeping. If their gills are still flicking every now and then, they should be fine.
When your axolotl is sick, stressed, or injured, room temperature can actually make things worse. The fridge method helps them heal by slowing down their metabolism and reducing bacteria growth — giving their body a chance to recover.
You can tell if an axolotl is sick by watching for loss of appetite, lethargy, curled or missing gill filaments, skin issues (lesions, white patches), poor balance (floating/tilting), red toes, or a curled tail tip, often signaling poor water quality (ammonia, nitrates, chlorine), stress, or impaction, with immediate water parameter checks and possible tubbing or vet visits needed for treatment.
Signs that your axolotl is stressed include tightly curled forward gills, small gills or lack of gill filaments, or the very tip of their tail curling or folding over on itself, scratching at the gills with their back leg, or swimming erratically and writhing.
Treatment involves improving water parameters, isolating the affected axolotl, and using antifungal or antibacterial medications as prescribed by a vet. Maintaining clean, well-oxygenated water and minimizing stress helps prevent recurrence.
Ensure your axolotl is not struggling to stay submerged and check for signs like loss of appetite or lethargy, which could point to illness. Regularly test the water parameters of the axolotl tank to maintain a healthy environment, as they can become ill from water that is too hot.
You may feed as much as the axolotl will consume within a few minutes. Earthworms must be cut into smaller pieces for juvenile axolotls. For example, you may feed a juvenile axolotl one nightcrawler per serving, cut into thirds, if it is a larger worm.
Normally the chin will protrude downward and there will be other issues associated with organ failure such as reddish colouration and other problems such as lack of appetite. Also, if the axolotl isn't eating and is looking inflated, then this can also be a sign of organ failure or impaction.
The best thing is to keep the water parameters perfect and temp cool. A bubbler also helps oxygenate the water, and fluff the gills. I definitely can tell a difference with mine since using it.
Mosaic axolotls are one of the rarest morphs and are highly sought after by enthusiasts and collectors. The mosaic pattern is a mix of two or more different colors or patterns, creating a patchwork appearance.
Have you seen your axolotl rubbing against objects, acting restless, or showing other signs of irritation? Keep ammonia and nitrites at 0 ppm, nitrates below 20 ppm. Maintain water temperature between 60–64°F (15–18°C) to reduce stress and promote healing.
Bare-bottom aquariums are not ideal for axolotls because they do not provide them with anything to grip. This can cause unnecessary stress and even sores on the end of their toes. Gravel is also not ideal because it can be easily swallowed and lead to an impaction that they may not be able to pass.
Axolotls prefer stagnant to slow moving water; strong currents can cause stress. A spray bar can help dissipate water flow across the surface of the tank. Large ornaments, rocks, or other aquarium decorations can also be used as a buffer when placed directly in front of the filter's current.