Can Red Tail Black Shark live with Rummy-Nose Tetra?
Case-by-case. Watch group sizes, tank size, and feeding zones.
Why Red Tail Black Shark and Rummy-Nose Tetra Don't Make an Easy Pair
They can coexist, but you need to manage the setup carefully. The temperament combination (semi-aggressive+peaceful) can work, but you will need to watch them at feeding time for the first week.
Red Tail Black Shark
Epalzeorhynchos bicolor
| Adult Size: | 5.0" |
| Temperament: | semi-aggressive |
| Min Tank: | 30 gal |
| Temperature: | 72-80°F |
| pH Range: | 6.5-7.5 |
Rummy-Nose Tetra
Hemigrammus rhodostomus
| Adult Size: | 2.0" |
| Temperament: | peaceful |
| Min Tank: | 20 gal |
| Temperature: | 75-82°F |
| pH Range: | 5.5-7.0 |
Water Parameter Overlap
| Parameter | Red Tail Black Shark | Rummy-Nose Tetra | Overlap |
|---|---|---|---|
| Temperature | 72-80°F | 75-82°F | 5°F ✓ |
| pH | 6.5-7.5 | 5.5-7.0 | 0.5 ✓ |
Compatibility Breakdown
Temperament Match: semi-aggressive + peaceful. Semi-aggressive → watch territory and feeding.
⚠️ Size Predation Risk: Red Tail Black Shark (5.0") vs Rummy-Nose Tetra (2.0"). A 3.0" gap — the larger fish will view the smaller fish as food.
Score: 50.0/100 (GOOD ≥80, CAUTION ≥50, RISKY <50).
🔧 Tank Setup Requirements (for Both)
- Minimum tank: 30 gallons — sized for the larger fish in the pair.
- Temperature: keep it between 75°F and 80°F.
- pH: maintain 6.5 – 7.0.
- Hiding spots: essential for Red Tail Black Shark — caves, plants, or driftwood to retreat when feeling stressed.
- Water changes: 25% weekly minimum. Two species mean double the bioload.
🔧 Tank Stocking Calculator
Enter tank size to calculate safe stocking levels:
Recommended Equipment
Based on tank size 30+ gallons:
High-quality flake food for community fish
Explore Related Checks
See what else works with these fish:
Accuracy note: This tool uses expert rules + FishBase.org data. Individual fish behavior varies — a semi-aggressive individual Red Tail Black Shark may act differently from its species average. Always observe, quarantine new arrivals for 2-4 weeks, and avoid overcrowding. If a pairing says CAUTION, start with a smaller group and a lid.