Can Electric Blue Crayfish live with Rummy-Nose Tetra?
High risk due to water mismatch, aggression, or predation.
Why Electric Blue Crayfish and Rummy-Nose Tetra Don't Make an Easy Pair
The size gap is 4.0" — Electric Blue Crayfish (6.0") and Rummy-Nose Tetra (2.0"). A fish that fits in another fish's mouth will eventually end up there.
Electric Blue Crayfish
Procambarus alleni
| Adult Size: | 6.0" |
| Temperament: | aggressive |
| Min Tank: | 30 gal |
| Temperature: | 65-80°F |
| pH Range: | 6.5-8.0 |
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 | Electric Blue Crayfish | Rummy-Nose Tetra | Overlap |
|---|---|---|---|
| Temperature | 65-80°F | 75-82°F | 5°F ✓ |
| pH | 6.5-8.0 | 5.5-7.0 | 0.5 ✓ |
Compatibility Breakdown
Temperament Match: aggressive + peaceful. One aggressive → predation/nipping risk.
⚠️ Size Predation Risk: Electric Blue Crayfish (6.0") vs Rummy-Nose Tetra (2.0"). A 4.0" gap — the larger fish will view the smaller fish as food.
Score: 45.0/100 (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 Rummy-Nose Tetra — 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:
Sinking food for crayfish and crustaceans
Explore Related Checks
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Accuracy note: This tool uses expert rules + FishBase.org data. Individual fish behavior varies — a aggressive individual Electric Blue Crayfish 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.