Can Foxface Rabbitfish live with Hillstream Loach?
High risk due to water mismatch, aggression, or predation.
Why Foxface Rabbitfish and Hillstream Loach Don't Make an Easy Pair
The size gap is 6.5" — Foxface Rabbitfish (9.0") and Hillstream Loach (2.5"). A fish that fits in another fish's mouth will eventually end up there.
Foxface Rabbitfish
Siganus vulpinus
| Adult Size: | 9.0" |
| Temperament: | peaceful |
| Min Tank: | 75 gal |
| Temperature: | 74-82°F |
| pH Range: | 8.1-8.4 |
Hillstream Loach
Sewellia lineolata
| Adult Size: | 2.5" |
| Temperament: | peaceful |
| Min Tank: | 20 gal |
| Temperature: | 64-75°F |
| pH Range: | 6.5-7.5 |
Water Parameter Overlap
| Parameter | Foxface Rabbitfish | Hillstream Loach | Overlap |
|---|---|---|---|
| Temperature | 74-82°F | 64-75°F | 1°F ✓ |
| pH | 8.1-8.4 | 6.5-7.5 | No overlap ✗ |
Compatibility Breakdown
Temperament Match: peaceful + peaceful. Both peaceful → minimal conflict.
⚠️ Size Predation Risk: Foxface Rabbitfish (9.0") vs Hillstream Loach (2.5"). A 6.5" gap — the larger fish will view the smaller fish as food.
Score: 10/100 (GOOD ≥80, CAUTION ≥50, RISKY <50).
🔧 Tank Setup Requirements (for Both)
- Minimum tank: 75 gallons — sized for the larger fish in the pair.
- Temperature: keep it between 74°F and 75°F.
- pH: no shared range. One species will be outside its tolerance regardless of what you set.
- Hiding spots: essential for Foxface Rabbitfish — 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 75+ gallons:
Dried seaweed sheets for marine herbivores
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 peaceful individual Foxface Rabbitfish 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.