Nannostomus marginatus, or Dwarf Pencilfish, is a small and peaceful species known for its distinctive horizontal stripes. Perfect for nano tanks and community setups.
Overview
Nannostomus marginatus, commonly known as the Dwarf Pencilfish, is a small, peaceful freshwater fish native to the slow-moving waters of the Amazon Basin in South America. This species is easily recognizable by its elongated body and prominent horizontal stripes that run the length of its body. Dwarf Pencilfish are an ideal choice for nano tanks and community aquariums due to their small size, typically reaching only 3-4 cm in length, and their calm, non-aggressive nature.
Tank Requirements
Dwarf Pencilfish thrive in well-maintained aquariums with a minimum capacity of 40 liters. They prefer soft, slightly acidic water with a pH range of 5.0-7.0 and a temperature between 24-28°C. These fish do best in densely planted tanks with plenty of hiding spots and subdued lighting, which mimics their natural habitat. Adding floating plants can help diffuse light and create a more comfortable environment. A gentle filtration system is recommended, as strong currents can stress these small fish. Regular water changes are essential to maintain water quality and keep the fish healthy.
Feeding and Diet
In the wild, Nannostomus marginatus feeds on small invertebrates and plant matter. In captivity, they should be offered a varied diet consisting of high-quality micro-pellets, finely crushed flakes, and live or frozen foods such as daphnia, brine shrimp, and micro-worms. These fish have small mouths, so food should be appropriately sized to ensure they can eat comfortably. Feeding them 2-3 times daily in small amounts will help maintain their health and vibrant coloration.
Care and Maintenance
Caring for Dwarf Pencilfish is relatively easy, making them suitable for both novice and experienced aquarists. Regular maintenance, including weekly water changes of 20-30%, is crucial for keeping the tank environment stable. These fish are sensitive to water quality, so it's important to monitor parameters closely and avoid sudden changes. They are generally hardy but can be prone to stress in poor conditions, so providing a calm, stable environment is key to their well-being.
Compatibility
Nannostomus marginatus is a peaceful species that does well in community tanks with other small, non-aggressive fish. Suitable tank mates include other small tetras, rasboras, Corydoras catfish, and small gouramis. They should be kept in groups of at least six individuals to encourage natural schooling behavior. Avoid keeping them with larger or more boisterous species that may intimidate or outcompete them for food.
Breeding
Breeding Dwarf Pencilfish in captivity is possible but can be challenging. A separate breeding tank with soft, acidic water and a temperature around 26°C is recommended. The tank should be densely planted with fine-leaved plants or spawning mops where the female can deposit her eggs. After spawning, the adults should be removed to prevent them from eating the eggs. The eggs typically hatch within 24-36 hours, and the fry should be fed infusoria or liquid fry food until they are large enough to eat baby brine shrimp or finely crushed flakes.