All fish / Characidae

Mexican tetra

Astyanax mexicanus

Also known as blind cave tetra, blind cave fish, mexican cave tetra, blind tetra, cave tetra, astyanax fasciatus mexicanus, anoptichthys jordani, ปลาตาบอด, ブラインドケーブ・カラシン, ikan buta, 盲眼鱼, 墨西哥丽脂鲤

This tetra comes in two forms: a silvery surface form with eyes, and a pale pink cave form that has no eyes and no pigment. The blind cave form is the one usually sold. It is popular because it is hardy, active and interesting to watch, and because it finds food easily using its lateral line and sense of smell.

Care at a glance

Care level

Easy

Temperament

Semi

Adult size

9 cm

Temperature

18 to 26 °C

pH

6.5 to 8

Smallest tank

100 litres

Keep as

Group of 6 or more

Diet

Omnivore: quality flakes and pellets, frozen bloodworm, brine shrimp and some vegetable matter

Swims

Bottom of the tank

Lifespan

10 to 15 years

Water

Freshwater

Wild range

Lower Rio Grande and Pecos River in Texas and New Mexico, south through northeastern and central Mexico

Breeding

It scatters eggs over plants or the substrate and does not look after them. Spawning is fairly easy in captivity, but the adults will eat the eggs, so remove them or use a mesh after spawning.

Good to know

It can nip the fins of slow, long-finned tankmates and is better suited to a cool or temperate tank. Cave and surface forms belong to the same species and can interbreed.