Can Lyretail Killifish live with Rummy-Nose Tetra?
Case-by-case. Watch group sizes, tank size, and feeding zones.
Why Lyretail Killifish and Rummy-Nose Tetra Don't Make an Easy Pair
They can coexist, but you need to manage the setup carefully. The temperature margin is tight — only 2°F of safe overlap, which leaves little room for thermostat drift.
Lyretail Killifish
Aphyosemion australe
| Adult Size: | 2.5" |
| Temperament: | peaceful |
| Min Tank: | 10 gal |
| Temperature: | 72-77°F |
| pH Range: | 6.0-7.0 |
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 | Lyretail Killifish | Rummy-Nose Tetra | Overlap |
|---|---|---|---|
| Temperature | 72-77°F | 75-82°F | 2°F ✓ |
| pH | 6.0-7.0 | 5.5-7.0 | 1.0 ✓ |
Compatibility Breakdown
Temperament Match: peaceful + peaceful. Both peaceful → minimal conflict.
Score: 70.0/100 (GOOD ≥80, CAUTION ≥50, RISKY <50).
🔧 Tank Setup Requirements (for Both)
- Minimum tank: 20 gallons — sized for the larger fish in the pair.
- Temperature: keep it between 75°F and 77°F.
- pH: maintain 6.0 – 7.0.
- Hiding spots: essential for Lyretail Killifish — 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 20+ gallons:
Tropical flake food for schooling tetras
Explore Related Checks
See what else works with these fish:
⚠️ Common Reasons This Pairing Fails in Practice
- Narrow temperature margin: Only 2°F of overlap means a stuck heater or seasonal temperature swing can push one species out of its comfort zone.
- Overcrowding: Even compatible species fail in tanks that are too small. Double the species means double the bioload — 25% weekly water changes are the minimum.
- Inadequate acclimation: Adding both species on the same day without quarantine is a common mistake. Always drip-acclimate new arrivals and quarantine for 2–4 weeks.
- Mismatched feeding: Lyretail Killifish is a carnivore while Rummy-Nose Tetra is a omnivore. Use targeted feeding zones and sinking vs. floating food to ensure both get proper nutrition.
Tools & Resources
Accuracy note: This tool uses expert rules + FishBase.org data. Individual fish behavior varies — a peaceful individual Lyretail Killifish 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.