Harlequin Lancer Catfish

Siluriformes sp.

Harlequin Lancer Catfish (Siluriformes sp.) — Easy care, Peaceful, under Catfish & Cory. Minimum tank in the app: 120 US gal min; aim for 75–81°F and pH 6–7.8. The Harlequin Lancer Catfish is ideal for aquarists seeking a low-maintenance, bottom-dwelling species that contributes to the tank's ecological balance.

Harlequin Lancer Catfish (Siluriformes sp.) in a planted freshwater aquarium
Care levelEasy
TemperamentPeaceful
Min tank size120 US gal min
pH range6–7.8
Temperature75–81°F
Max size11.8 in (30.0 cm)
Captive lifespan12–20 years
SchoolingNo

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.

Natural distribution

Mostly South America / Africa

  • South America
  • Africa

Regional colours match the stocking calculator’s origin map.

Harlequin Lancer Catfish Tank Setup

A spacious layout is essential, with ample hiding spots created by rocks, driftwood, and plants to encourage exploration. A sandy substrate is preferable for comfort, while moderate water flow can mimic natural conditions. Adequate lighting should be diffuse to reduce stress, fostering a serene environment that promotes healthy activity levels.

What Do Harlequin Lancer Catfishs Eat?

As an omnivorous bottom feeder, the Harlequin Lancer Catfish thrives on sinking pellets and a variety of foods, including vegetable matter. Competition at feeding times is low, allowing for relaxed eating habits.

Harlequin Lancer Catfish Tank Mates

Ideal companions include similarly sized, non-aggressive species that occupy mid to upper water zones, preventing competition for space. Fish that are overly aggressive or very small may provoke stress or pose predation risks. Intraspecies interactions are generally peaceful, but overcrowding can lead to stress, so maintaining a balanced population is crucial.

Are Harlequin Lancer Catfishs Good for Beginners?

In App-aquatic we file this under easy care. That still means a cycled tank, realistic stocking, and parameters that do not swing every weekend. Aquarists often underestimate the need for tank size and filtration, leading to poor water quality that can compromise health. neglecting to provide adequate cover may result in stress and altered behavior, as these fish rely on security during the day.

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