More info
Datasheet
| Minimum Tank Size | 40 litres / 10.57 US gallons |
| Maximum Size | 3.0cm / 1.18inches |
| Temperature | 22°C / 71.60°F - 28°C / 82.40°F |
| Hardness | 1.01dgH / 18ppm - 10.03dgH / 179ppm |
| pH | 5.0-7.0 |
General Description
The Twostripe Pencilfish (Nannostomus Digrammus) belongs to the Lebiasinidae family within the Characiformes order. This species typically grows up to 3.0cm in size and is known for its two dark lateral body stripes and the presence of an adipose fin. It is a micropredator in nature, feeding on tiny invertebrates and zooplankton.
Aquarium Setup
For optimal care, Twostripe Pencilfish should be kept in a heavily planted tank with a dark substrate that encourages natural behavior and reduces skittishness. The addition of floating plants, driftwood branches, and dried leaf litter aids in establishing microbe colonies beneficial for the ecosystem. Gentle filtration, preferably with an air-powered sponge-style unit, is recommended. Water conditions should be maintained at a temperature of 22-28°C, pH of 5.0-7.0, and hardness of 18-179ppm (see table).
Behaviour
Twostripe Pencilfish are very peaceful but may not thrive in community tanks due to their small size and timid nature. They are best kept with similarly-sized, peaceful characids, smaller callichthyid or loricariid catfishes, or as dither fish for Apistogramma spp. They exhibit shoaling behavior and may display aggression within their group, but this rarely extends to tankmates. Larger groups, ideally 10 or more, spread out aggression among individuals and promote bolder and more natural behavior.
Feeding and Diet
Twostripe Pencilfish are micropredators that feed on tiny invertebrates and zooplankton in their natural habitat. In captivity, they accept dried foods but should also be offered daily meals of small live and frozen fare like Artemia nauplii, Moina, and grindal worms to ensure a balanced diet.
Reproduction & Dimorphism
Information on the reproduction of Twostripe Pencilfish is currently unreported. Adult males are characterized by their highly-modified, extended anal fins, more vibrant coloration, and slimmer bodies compared to females.
Habitat and Distribution
Native to the central Amazon basin, specifically in the Madeira, Branco, Trombetas, and Tapajós river drainages, Twostripe Pencilfish inhabit sluggish tributaries, small rivers, and swampy areas with dense aquatic vegetation. There have been reports of similar-looking fish with additional dark stripes from Colombia and possibly Peru.