Rubytail Pencilfish – Nannostomus rubrocaudatus L 2.5–3.5 cm | Ruby Red Dwarf Pencilfish

The Rubrocaudatus Pencilfish (Nannostomus rubrocaudatus), also known as the Ruby Pencilfish, is one of the most vibrantly colored dwarf tetras in South America. With its luminous red body, shimmering blue reflections, and elegant body shape, it is one of the most beautiful species of its genus. In the aquarium, it impresses with its calm, floating movement and harmonious schooling behavior.

The Ruby Pencilfish originates from the blackwater streams of the upper Amazon basin and prefers soft, slightly acidic water. In planted, dimly lit aquariums, its vibrant colors are particularly enhanced.

🌿 Characteristics & Care:

🐠 Size: 2.5–3.5 cm (L)
🌎 Origin: South America (Peru, Brazil – Amazon region)
🌡️ Temperature: 24–28 °C
💧 pH-Value: 5.0–6.8
⚖️ Total Hardness: up to 8 °dGH
🐟 Social Behavior: Peaceful schooling fish, best in groups of 8–10 individuals
🌾 Aquarium: From 60 l, densely planted with shaded areas and dark substrate

🍽️ Feeding:
Eats finest live and frozen food (e.g., Artemia nauplii, Cyclops, Daphnia). High-quality micro-granules are also accepted once accustomed.

💡 Tip:
A blackwater aquarium with Indian almond leaves, alder cones, and subdued lighting impressively highlights the ruby-red coloration and natural behavior.

👉 Conclusion:
The Rubrocaudatus Pencilfish (Nannostomus rubrocaudatus) is a peaceful, brightly colored dwarf tetra with intense red coloration – perfect for lovers of colorful South American species in nano or community aquariums.