Species description

Care, breeding and tankmates

Fish profile

Temperament

Semi-aggressive

They are timid, peaceful fish that spend their time quietly hovering. They are easily intimidated by boisterous tank mates and require a tranquil environment. In a peaceful species setup, they are incredibly serene and mesmerizing to watch.

Diet

Omnivore

They are micro-predators that specialize in feeding on tiny surface-dwelling insects. In the aquarium, they will readily accept floating micro-pellets and crushed flakes. Live foods such as fruit flies and mosquito larvae are highly relished.

Sex ratio

School

Keeping a balanced group of both sexes encourages natural and fascinating behaviors. Males are slightly slimmer and more colorful, often engaging in harmless displays. A large school provides the best visual impact and social stability.

Feeding frequency

Twice daily

Feed them small amounts two or three times daily to mimic natural foraging. Because they feed exclusively at the surface, ensure food floats long enough. Careful observation is needed to confirm all individuals are eating.

Bioload

The Brown Pencilfish, or Diptail, has a remarkably low bioload impact. Their diminutive size makes them perfect for smaller, densely planted aquariums. Excellent water quality must still be maintained despite their low waste output.

Flow

Stagnant

They require very gentle flow, reflecting their natural still-water swamp habitats. Strong currents will disrupt their unique oblique swimming posture and cause stress. Baffling the filter output is highly recommended to create a calm surface.

Reproduction

Oviparous

Breeding is challenging and requires a dedicated setup with very soft water. They lay their eggs directly on the underside of broad aquatic leaves. Adults must be removed post-spawning as they will quickly consume the eggs.

Compatibility & tankmates

They are exceptionally peaceful and should only be kept with similarly gentle species. Small tetras, dwarf corydoras, and otocinclus make excellent, harmonious tank mates. Avoid housing them with fast, aggressive feeders that might outcompete them.

Tank level

Top

They are obligate surface dwellers that rarely venture deeper into the tank. They are famous for hovering at an oblique, tail-down angle just below the surface. Floating vegetation is crucial to provide them with a sense of security.