Dwarf pencilfish

Care at a glance

Overview

Keep dwarf pencilfish in a group of at least six, in a tank of around 45 liters or more. They hold the middle of the water and move in a slow, deliberate way rather than darting. Their mouths are tiny, so feed small foods like crushed flakes, micro-pellets, baby brine shrimp, and daphnia. They are peaceful and best matched with other small, calm fish in soft, acidic water.

In the wild

Dwarf pencilfish live in slow, heavily planted blackwater across Peru, Colombia, and Brazil, in streams and flooded forest with leaf litter underfoot. The water is soft, acidic, and dark with tannins. A tank with dim lighting, fine plants, driftwood, and dried leaves suits them, with a pH on the low side, down toward 5 to 7. Keep flow gentle and the water warm.

Good to know

This is a pencilfish in the family Lebiasinidae, one of the smaller species at around 2.5 cm. The slim body carries a dark horizontal stripe with bordering lines and red on the fins. It is an egg scatterer, and breeding takes some effort. It does best in warm, soft, acidic water in the mid to high 20s C.

Did you know

Like other pencilfish, they switch their coloring at night. The crisp daytime stripe breaks up into a blotchy pattern once the lights go out, then snaps back in the morning.

Related species

• 

  Barred pencilfish

  Nannostomus espei

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

• 

  Coral red pencilfish

  Nannostomus mortenthaleri

  1.2 in (3 cm)15 gal (55 L)75–82°F (24–28°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)
• One-lined Pencilfish

  Nannostomus unifasciatus

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