Our Guide To Keeping Dwarf Pencilfish

1. About Fish Species:

   • Scientific name: Nannostomus marginatus
   • Common name: Dwarf Pencilfish
   • Family: Lebiasinidae
   • Origin: Amazon Basin (Brazil, Guyana, Suriname, and Peru)
   • Adult length: 2.5 to 3.5 cm
   • Lifespan: 3 to 5 years
   • Diet: Omnivore (micro-predator)
   • Care Level: Moderate
   • Temperament: Peaceful

2. Tank Setup:

   • Dwarf Pencilfish prefer a calm, heavily planted aquarium with dim lighting and a dark substrate to enhance their colours and reduce stress.
   • Floating plants like Salvinia or Frogbit help diffuse the light and mimic their shaded natural habitat.
   • A minimum tank size of 40L is suitable for a small group.

3. Water Parameters:

   • Temperature: 22–28°C (72–82°F)
   • pH: 5.5 to 7.0
   • Hardness: Soft to moderately soft (2–10 dGH)

4. Filtration and Water Flow:

   • Use a gentle sponge or hang-on-back filter with low flow. Pencilfish dislike strong currents.
   • Ensure excellent water quality through frequent small water changes.

5. Diet:

   • They feed on small live and frozen foods like daphnia, baby brine shrimp, and micro worms.
   • They may accept finely crushed flake or micro pellets, but live foods help bring out natural behaviour and coloration.

6. Tank mates:

   • Keep in groups of at least 6 to encourage natural schooling and reduce stress.
   • Ideal companions include other peaceful nano species like small tetras, rasboras, pygmy corydoras, and otocinclus.
   • Avoid boisterous or larger fish that may outcompete them for food.

7. Behavior and Compatibility:

   • Dwarf Pencilfish are calm and slightly shy, often hovering near the mid-to-upper tank levels.
   • Males may display gentle territorial behaviour during courtship, but they are generally peaceful.
   • Best kept in a species-only or quiet community setup.