Compatibility Overview
Hillstream Loach and Percula Clownfish are generally not recommended to be housed together. The issues listed above — whether water parameter incompatibility, predation risk, or aggression — create conditions where one or both fish are likely to suffer harm or chronic stress.
| Factor | Hillstream Loach | Percula Clownfish | Verdict |
|---|---|---|---|
| Temperature | 64–73°F | 75–82°F | ❌ No overlap |
| pH Range | 6.5–7.5 | 8.0–8.5 | ❌ No overlap |
| Temperament | semi | semi | ⚠️ Monitor |
| Adult Size | 2.0 in | 3.1 in | ✅ Similar |
| Min. Group | 1+ | 1+ | See below |
| Min. Tank Size | 29 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Hillstream Loach — Aquarium species
Sewellia lineolata, known as the Hillstream Loach, is a fascinating species for aquarists. These fish require a well-oxygenated, clear water environment with plenty of hiding spots. With a lifespan of 7 years, they are a long-term commitment. Their olive green color and slender body shape add a unique aesthetic to the tank. Despite their moderate activity le
→ Full Hillstream Loach care guide
Percula Clownfish — Aquarium species
The Percula Clownfish, also known as the False Percula, is a popular beginner fish due to its hardiness and striking coloration. These fish are best kept in a saltwater tank with a minimum size of 30 gallons and compatible tankmates. They are peaceful, non-aggressive and do well in groups with other compatible species. Regular water quality maintenance is es
Frequently Asked Questions
Can Hillstream Loach live with Percula Clownfish?
Generally not recommended. Hillstream Loach and Percula Clownfish are generally not recommended to be housed together. The issues listed above — whether water parameter incompatibility, predation risk, or aggression — create conditions where one or both fish are likely to suffer harm or chronic stress.
What tank size do I need for Hillstream Loach and Percula Clownfish together?
A minimum of 29 gallons is recommended for keeping Hillstream Loach and Percula Clownfish together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Hillstream Loach and Percula Clownfish?
No overlap
Is a Hillstream Loach aggressive toward a Percula Clownfish?
Hillstream Loach is semi and Percula Clownfish is semi. These animals require different water types and cannot share one aquarium.
Related Compatibility Guides
Compatibility score breakdown
The overall score is weighted across water chemistry, behavior, adult size, swimming zone, and social needs. A score is a planning aid—not a guarantee for individual fish.
| Factor | Score |
|---|---|
| Temperature | 0/100 |
| Ph | 0/100 |
| Temperament | 62/100 |
| Adult Size | 100/100 |
| Swim Zone | 92/100 |
| Social Needs | 92/100 |
Tank size scenarios
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 29 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 40 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 55 gal | Best when keeping larger schools or reducing territorial pressure. |