How to care for Mexican Walking Fish

Mexican walking fish are fascinating creatures looking, and often acting, like miniature pre historic monsters. These animals can grow up to 30cm in size make excellent pets.

Axolotls are the larval stage of a salamander, and are different from other amphibians in that they have the ability to reproduce while remaining a sexually mature larva. They also have the ability to undergo metamorphosis (similar to a tadpole changing into a frog) and change to an air breathing, land dwelling, salamander, but this very seldom occurs. It seems that most strains have now lost the ability to metamorphose.

Mexican walking fish come in various colours, including dark brown, olive, black, albino and golden forms, which have bright pink gills) and a piebald (spotted) form, which is seldom seen.

The name walking fish refers to the animal’s habit of walking whilst under water. They should not be removed from their aquarium and forced to crawl on land, as they cannot breathe out of water.

Housing

Axolotis are best housed in conditions similar to goldfish, as their water requirements are very much the same. They prefer a cool environment with a tolerated range of between 10 and 20 deg Celsius and an ideal temperature of 12 - 18 deg Celsius.

An aquarium 60cm x 30cm x 30cm will house a full grown pair of axolotls. The tank should be aerated and filtered, as axolotis extract oxygen from water through their gills, and the quality and clarity of water is important to their well being. A monthly partial water change of approx.1/3 helps freshen the water and keeps organic loads down to a safe level. The pH of their water should be kept about 7.0 - 7.5. Using a little crushed coral or shell grit is a simple way of achieving this. Low pH levels are detrimental to their health. Lighting is best kept moderately dim, as axolotls are somewhat nocturnal in nature, with albino forms becoming stressed under bright light.

Feeding

Earthworms are by far the most suitable food for walking fish. When fed earthworms they remain healthy and vigorous and are most likely to reach their full life expectancy. To ensure earthworms cantt bury out of reach in the aquarium gravel, where they would die within a few days, its best to limit gravel depth to a single layer of smooth standard aquarium gravel only a few millimetres thick. Therefore the worms remain visible and available to the axolotis.

An occasional feed of finely cut lean beef may be offered, but if fed regularly the fat in red meat would almost certainly lead to health problems such as fat accumulation in internal organs. Sinking fish pellets may also be offered but be careful they don’t break up and pollute the water.

Feeding every second day is usually sufficient. Requirements for food vary with temperature; they normally refuse to eat if the temperature falls below 10°C or goes much above 20°C. Their preferred eating time is at dusk. Always remember to remove any uneateri food or pollution will occur.

Breeding

Male and female axolotls are not difficult to differentiate when sexually mature, which is at about 12 months of age. The male shows a swelling around the cloaca area (the sexual opening) between the back legs. Males have a longer tail and the head is narrower. The female lays between 300 to 1000 eggs when she spawns in early spring. Eggs hatch in about 2 weeks at a temperature of 14-18°C. Parents should be removed from the tank after spawning and young raised on live food. Newly hatched brine shrimp or sifted water fleas (baphnia) are quite suitable at first. Later, juveniles will take live aquatic “black” worms (tubifex).

Compatibility

When a large number of axolotls are kept together, as is likely to occur in a pet shop or aquarium shop, it is important to provide plenty of hiding places. Rocks, plants arid cut plastic pipes are suitable. Individuals may attack others in the tank if sufficient shelter is riot provided. it is most interesting, that in the event of a limb or portion of the animal being bitten off, it will regenerate. The damaged individuals are best isolated and given extra food and attention. The regeneration process seems to be more rapid at lower temperatures. Axolotls have a large wide mouth, well adapted for preying on fish, and therefore fish should riot be kept in the same aquarium.

Life Span

Given the right conditions, your axolotis should give you 10-15 years of enjoyment. They are certainly one of the world’s most interesting creatures