Rummynose Tetra
Rummynose Tetra
Rummynose Tetra (Petitella bleheri) is one of the great schooling fish of the freshwater hobby — a slim, elegant tetra with a vivid red head, iridescent silver body, and boldly striped black-and-white tail. In a large group, Rummynose Tetras school with military precision, turning as one unit in a tight formation that is one of the most spectacular behaviors available in freshwater aquariums. Worth noting: three different species are sold as 'Rummynose' — this is Petitella bleheri, the most widely available true Rummynose.
Feeding & Care Tip: Hikari Micro Pellets (crushed or soaked) 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. Feed small amounts 2–3 times daily in a calm environment.
Native to the Rio Negro and Rio Meta drainages. Named for Heiko Bleher, the legendary German explorer and fish collector. The red head coloration is not caused by pigment but by visible blood vessels close to the surface of the translucent skin — making it one of the most direct visual indicators of health and stress available in any aquarium fish.
Keep in groups of at least 10 — the larger the school, the tighter and more synchronized the schooling behavior. Groups of 20 or more produce the famous torpedo-shaped tight school. The red head coloration functions as a direct water quality indicator — it fades noticeably when conditions deteriorate.
Require a mature, stable aquarium — sensitive to water quality fluctuations. Their sensitivity to conditions makes them excellent indicator fish, but also means they should be among the last species added to any setup.
Care & Ideal Parameters
| Difficulty | Moderate |
| Temperament | Peaceful — active schooling |
| Typical Adult Size | 2.0 inches (5 cm) |
| Min. Group Size | 10 minimum — 20+ for tight schooling |
| Ideal Temp | 74–81°F (23–27°C) |
| Ideal pH | 6.0–7.0 |
| Ideal GH | 1–8 dGH |
| Ideal KH | 0–4 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 | Rio Negro and Rio Meta drainages, Brazil and Colombia |
| Notes | Petitella bleheri — most common of three 'Rummynose' species in trade. Named for explorer Heiko Bleher. Red head = visible blood vessels — direct stress indicator. Tight schooling most spectacular in groups of 20+. |
