#11521 Cueva de El Pachón, San Luis Potosí, Mexico

Aquarium information

Aquarium description

Set-up date

March, 2026

Aquarium decoration

The aquarium recreates the subterranean pools of Cueva de El Pachón using a layout inspired by the limestone cave formations of the Sierra de El Abra, Mexico. Chicken Bone Stone was selected for its porous texture and natural resemblance to eroded karst limestone, allowing the construction of caves, crevices, and sheltered passages similar to those found in the natural habitat.

A fine, light-coloured sand substrate reproduces the cave floor and contrasts with the limestone formations. No aquatic plants were included, reflecting the complete absence of vegetation in the permanently dark cave environment. The hardscape was arranged to create open swimming areas while providing numerous refuges, closely matching the underwater structure of the natural habitat.

Subdued lighting enhances the cave-like atmosphere and highlights the distinctive appearance and natural behaviour of the Blind Cave Tetra (Astyanax mexicanus).

Aquarium equipment

Aquarium: 60 × 45 × 40 cm.

Filtration: SunSun HW-304B external canister filter providing multi-stage mechanical and biological filtration.

Heating: Thermostatically controlled heater maintained at 24 °C.

Lighting: Low-intensity Chihiros Z LED lighting to simulate the dim conditions of a subterranean habitat while allowing observation of the fish.

The equipment was selected to maintain excellent water quality, stable water parameters, and gentle water movement characteristic of underground cave pools.

Fish care

The aquarium houses only Astyanax mexicanus (Blind Cave Tetra), maintaining ecological consistency with the referenced biotope. The rockwork provides numerous caves and sheltered areas that encourage natural exploration and social interactions.

The fish are fed a varied diet consisting of high-quality pellets, frozen bloodworms, brine shrimp, and other protein-rich foods. Water quality and fish behaviour are monitored regularly, while stable temperature and water chemistry are maintained to minimise stress and promote long-term health.

Fish:

• Astyanax mexicanus – Blind cave morph (El Pachón population) (Characidae)

Plant care

No aquatic plants are maintained in this aquarium because the referenced natural habitat is a permanently dark limestone cave where aquatic vegetation is absent. Their omission is intentional and preserves the ecological authenticity of the recreated biotope.

Water care

Approximately 20% of the aquarium water is replaced every 10–14 days using conditioned water matched to the aquarium’s temperature and chemistry. Water parameters, including pH, conductivity, hardness, and temperature, are monitored regularly.

The external filter is serviced only when necessary to preserve beneficial bacterial colonies. Gentle water circulation and high oxygen levels are maintained to replicate the stable conditions of the natural cave habitat while ensuring excellent water quality for the fish.

Dimensions

Length

60 cm

Depth

45 cm

High

40 cm

Volume

100 L