Natural Habitat & Origin
Rummy nose tetras are found in the blackwater tributaries of the Amazon basin, particularly in Brazil and Colombia. These dark, tannin-rich waters are soft, acidic, and warm — conditions that should be replicated in captivity for best results.
Tank Setup
- Tank size: 20 gallons minimum for a school of 8–10. A 40-gallon breeder is ideal for a school of 15–20.
- Substrate: Dark sand or fine gravel — enhances their coloration dramatically
- Plants: Densely planted with plenty of open swimming space in the center. They need room to school.
- Driftwood: Releases tannins that soften water and create their preferred blackwater conditions
- Lighting: Moderate to subdued
- Flow: Gentle to moderate — they come from slow-moving waters
Water Parameters
- Temperature: 75–84°F (24–29°C)
- pH: 5.5–7.0 (soft, acidic water preferred)
- Ammonia/Nitrite: 0 ppm
- Nitrate: below 15 ppm (they are sensitive to nitrate buildup)
- GH: 2–6 dGH
Rummy nose tetras are excellent water quality indicators. A bright, cherry-red nose means your water is pristine. If the red fades to pink or white, something is off — check your parameters immediately.
Diet & Feeding
- Staple: High-quality micro pellets or crushed tropical flakes
- Supplements: Frozen brine shrimp, daphnia, cyclops — 2–3 times per week
- Tip: Feed small amounts that they consume within 60 seconds. Their small mouths mean they need appropriately sized food.
Schooling Behavior
This is where rummy nose tetras truly excel. While many schooling fish loosely group together, rummy noses form incredibly tight, synchronized schools that move as one. A school of 15+ in a 40-gallon planted tank is one of the most mesmerizing sights in freshwater fishkeeping.
Keep at least 8, but 12–15 is where their schooling behavior becomes truly spectacular. Never keep fewer than 6 — they become stressed, pale, and hide constantly.
Tank Mates
Ideal community fish. They pair beautifully with:
- Other tetras (cardinal, ember, neon) for a multi-species school effect
- Corydoras catfish and otocinclus on the bottom
- Angelfish (in larger tanks — the angels may occasionally chase but rarely catch them)
- Dwarf gouramis as a centerpiece
- Cherry shrimp and nerite snails
The Red Nose as Health Indicator
The intensity of the red coloration on their nose directly correlates with their health and water quality:
- Bright cherry red: Healthy, happy, excellent water quality
- Pale pink: Mild stress — check water parameters, may be acclimating
- White/colorless: Significant stress or illness — immediate water testing needed
- Note: Color naturally fades at night and returns within minutes of lights on
Frequently Asked Questions
Why are my rummy nose tetras pale?
Most likely a water quality issue. Test ammonia, nitrite, nitrate, and pH. They can also pale from stress during acclimation (give them 1–2 weeks to settle in) or disease. Ensure your tank is fully cycled and mature before adding them.
How many rummy nose tetras should I keep?
At minimum 8, ideally 12–15+. Larger schools display dramatically tighter schooling formation. In groups under 6, they become stressed and lose color.