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Tetra Aquarium Fish

Blind Cave Tetra

Blind Cave Tetra - Origins

Blind Cave Tetra Astyanax fasciatus mexicanus
Blind Cave Tetra

The Blind Cave Tetra is also known as the Mexican Tetra, Blind Cave Fish or the Silvery Tetra. They are a good beginner's fish, as they can tolerate great variation in water temperature and quality. The scientific name was originally Anoptichthys jordani, but it is now classified as Astyanax fasciatus mexicanus. The Blind Cave Tetra is a northern sub species and is found in cave waters in Texas and Mexico. The eyed version extends from Central to South America.

Blind Cave Tetra Astyanax fasciatus mexicanus
Blind Cave Tetra

Blind Cave Tetra - No Eyes

The body is a flesh/silvery color without features and the fins are colorless. The dorsal fin has a broad arch to it. The main feature of the Blind Cave Tetra is an absence of eyes. They are born with eyes, but the sight deteriorates quickly and the eyes become distorted and covered over within a few weeks. They navigate in darkness quite well and have well developed taste buds. This schooling fish has an ability to avoid bumping into other fish, which is not clearly understood.

Blind Cave Tetra - Aquarium Setup

Blind Cave Tetras should be provided with dim lighting and small to medium size gravel. Or, better yet, give them some caves. Plants are not essential. The tank should be covered as Blind Cave Tetras will jump when they are stressed. They eat flake foods, freeze dried bloodworms and live brine shrimp.

Blind Cave Tetra - Compatibility

Blind Cave Tetras are one of the more aggressive tetras and they will nip fins. They should be kept with aggressive larger tetras, such as the Buenos Aires Tetra, the Colombian Tetra, the Serpae Tetra and the Silver Tip Tetra. They are definitely not good companions for smaller tetras and guppies.

The Blind Cave Tetra is compatible with the Buenos Aires Tetra, Corydoras Catfish, Danios, Large Tetras, Mollies, Platies, Plecostomus, Serpae Tetra, Silver Dollar, Silver Tip Tetra, Swordtails

Blind Cave Tetra Astyanax fasciatus mexicanus
Blind Cave Tetra

Blind Cave Tetra - Breeding

The females are larger and broader, especially when laden with eggs. There is no distinguishing color difference between males and females. If differentiating the sexes is difficult, the best way to breed Blind Cave Tetras is to start with a group of about 6 and let them choose pairings. They are typical tetra egg layers. Parents should be separated and fed live foods prior to spawning. A drop in water temperature may induce breeding. Up to one hundred eggs can be scattered throughout the breeding tank. The parents should be removed after spawning. The eggs will hatch in a couple of days and the fry will be ready for brine shrimp and finely ground flake foods within a week.

Blind Cave Tetra - Profile

  • Scientific Name: Astyanax fasciatus mexicanus

  • Family: Characin

  • Temperature: 20 - 30 C; 68 - 86 F

  • pH: 6.0 - 7.8

  • Size: 9 cm; 3.5 inches

  • Life Span: 5 years

  • Breeding: Normal, Egg Layer