Brown Tailed Pencilfish
Brown Tailed Pencilfish
Brown Tailed Pencilfish (Nannostomus eques) is the most distinctive pencilfish in terms of body posture — where other Nannostomus species hold a moderate oblique tilt, N. eques is virtually vertical at rest, hovering nose-up like a living exclamation point. Also called the Hockey Stick Pencilfish. A single reddish-brown lateral stripe runs the full length of the body.
Feeding & Care Tip: Hikari Micro Pellets (crushed or soaked briefly) and Sera Vipan Baby make excellent daily staples. Supplement 2–3× per week with Hikari Frozen or Freeze-Dried Baby Brine Shrimp and Hikari Frozen Daphnia. Pencilfish are slow, deliberate feeders — avoid fast tankmates that will outcompete them. Feed small amounts 2–3 times daily.
All Nannostomus species inhabit the blackwater and clearwater streams, lakes, and flooded forests of the Amazon and Orinoco basins — soft, acidic, tannin-stained water with dense vegetation and leaf litter. A mature blackwater setup with Indian almond leaves, dark substrate, and very soft slightly acidic water produces the most vivid coloration. Males are territorial with each other — keep more females than males and provide visual breaks with dense planting.
The oblique resting posture — head elevated, body angled downward at roughly 45 degrees — is a characteristic behavior of the Nannostomus genus. Schools adopt synchronized oblique positions at rest, which is both fascinating to observe and unmistakable once seen. The angle varies by species — some hold a gentle tilt while others are nearly vertical. N. eques takes the oblique posture to the extreme — nearly vertical at rest, a school appears to be a collection of floating twigs. Keep in groups of at least 8.
One of the most distinctive nano fish available — the vertical posture and elongated body create a fish like no other in the hobby.
Care & Ideal Parameters
| Difficulty | Easy — Moderate |
| Temperament | Peaceful — slow feeder; avoid fast tankmates |
| Typical Adult Size | 2.0 inches (5 cm) |
| Min. Group Size | 8 minimum — more females than males |
| Ideal Temp | 73–82°F (23–28°C) |
| Ideal pH | 5.0–7.0 |
| Ideal GH | 0–10 dGH |
| Ideal KH | 0–5 dKH |
| Staple Food | Hikari Micro Pellets (crushed/soaked); Sera Vipan Baby |
| Treat / Supplement | Hikari Frozen or Freeze-Dried Baby Brine Shrimp; Hikari Frozen Daphnia |
| Origin | Amazon and Orinoco basins, South America |
| Notes | Also Hockey Stick Pencilfish. Most extreme oblique posture of any Nannostomus — nearly vertical at rest. Single reddish-brown lateral stripe. |
