Description

Two-Saddled Catfish (Hoplisoma weitzmani)

Hoplisoma weitzmani, commonly known as the Two-Saddled Catfish or Weitzman’s Catfish, is a small, peaceful species of armoured catfish (belonging to the Callichthyidae family). It was previously classified under the genus Corydoras. Native to the upper Amazon basin, particularly in Peru and Colombia, this fish is prized for its distinctive markings and gentle nature, making it an excellent addition to a community tank.

Key Characteristics and Temperament

• Size: Typically reaches an adult length of only $4\text{ cm}$ to $5\text{ cm}$.
• Appearance: Features a silver-to-cream body with highly distinctive markings: two prominent black, saddle-like bands running vertically over the body, one near the dorsal fin and one near the tail.
• Temperament: Extremely peaceful and non-aggressive. Like all catfish in this group, they are busy, bottom-dwelling scavengers. They are diurnal but are often most active during the early morning and evening hours.

Aquarium Requirements and Habitat Setup

These catfish thrive best when their tank replicates the soft, acidic, and well-oxygenated conditions of their native jungle streams.

1. Water Parameters

• Temperature: 22∘C to 26∘C (72∘F to 79∘F). Consistent temperature is key.
• pH: Slightly acidic to neutral, ideally $6.0$ to $7.2$.
• Hardness ($\text{dH}$): Soft water is preferred, up to $10\text{ dH}$.

2. Tank Size and Filtration

• Minimum Tank Size: A standard aquarium of $60\text{ litres}$ ($15\text{ gallons}$) is suitable for a small shoal of 6-8 fish. A larger footprint (floor area) is always better than a deeper tank, as they spend all their time on the bottom.
• Filtration: Use a reliable filter system that provides excellent mechanical and biological filtration. The water current should be moderate, and the water must be clean and well-oxygenated.

3. Substrate and Décor

• Substrate (Crucial): Sand is the only suitable substrate. Hoplisoma weitzmani frequently sifts through the substrate with their sensitive barbels to find food. Gravel can damage their barbels, leading to infection.
• Décor: Provide ample hiding spots using smooth driftwood, caves, and dense planting. Floating plants are highly recommended as they diffuse overhead lighting, mimicking the shady environment they prefer and making them feel secure.

Diet and Social Behaviour

Feeding

• Hoplisoma weitzmani are omnivorous and should be fed a varied diet to ensure optimal health and colouration. As they are bottom-dwellers, all food must be sinking.
• Staple: High-quality sinking pellets or wafers specifically formulated for catfish.
• Live/Frozen Foods: Offer supplements of small live or frozen foods, such as bloodworms, Daphnia, and Tubifex worms, several times a week.
• Vegetables: They will sometimes accept blanched vegetables, such as courgette (zucchini) or shelled peas.

Social Needs

• Shoaling Fish: These are obligate shoaling fish and should never be kept alone. A minimum group of six individuals is required, but a larger shoal of 10 or more will encourage more natural behaviour and reduce stress.
• Tank Mates: Due to their small size and peaceful nature, choose equally calm and small-to-medium-sized tank mates. Good companions include small tetras (like the Cardinal or Neon Tetra), small Rasboras, and other small, non-aggressive fish. Avoid large, boisterous, or aggressive fish.