Coral red pencilfish

Care at a glance

Overview

Keep them in a shoal of six or more in a small planted tank of about 55 liters, where the males will color up and spar over rank without doing harm. They hold the middle of the water and are peaceful, so pair them only with other gentle, small species. Aim for the mid to high 20s C and a soft, acidic to neutral pH. Their mouths are small, so feed micro foods like crushed flake, micro-pellet, and tiny live or frozen items.

In the wild

Coral red pencilfish come from slow, clear streams in the Peruvian Amazon, around the Rio Nanay. The water is soft and acidic, full of leaf litter, roots, and fine plants. A blackwater-style setup with dim light, tannins, and lots of planting suits them and brings out their red. Gentle flow only, since these are small, delicate fish.

Good to know

This pencilfish sits in the family Lebiasinidae and stays tiny at around 3 cm. Males show the deepest red, while females are paler and rounder. It was only described in 2001, and it is a micropredator that eats very small invertebrates in the wild. Breeding is possible but takes effort.

Did you know

Rival males put on a near-constant color show, sparring and flaring to sort out rank, and they turn their brightest red during these standoffs. A single male kept alone never reaches that intensity because there is nobody to compete with.

Related species

• 

  Barred pencilfish

  Nannostomus espei

  1.2 in (3 cm)15 gal (55 L)72–82°F (22–28°C)

• 

  Three-lined pencilfish

  Nannostomus trifasciatus

  1.3 in (3.3 cm)15 gal (55 L)72–82°F (22–28°C)

• 

  Hockeystick pencilfish

  Nannostomus eques

  1.4 in (3.5 cm)15 gal (55 L)72–82°F (22–28°C)
• Twostripe pencilfish

  Nannostomus digrammus

  1.4 in (3.5 cm)12 gal (45 L)75–82°F (24–28°C)

• 

  Dwarf pencilfish

  Nannostomus marginatus

  1 in (2.5 cm)12 gal (45 L)72–82°F (22–28°C)
• One-lined Pencilfish

  Nannostomus unifasciatus

  1.6 in (4 cm)17 gal (65 L)73–82°F (23–28°C)