Hillstream Loach and Lionfish Compatibility Overview
Hillstream Loach and Lionfish are generally not recommended to be housed together. One of these is a marine species and the other is not; they cannot share one aquarium. The adult size gap creates a meaningful predation risk. Review the behavior and water details before deciding whether to attempt the pairing.
| Factor | Hillstream Loach | Lionfish | Verdict |
|---|---|---|---|
| Temperature | 68โ75ยฐF | 72โ82ยฐF | โ ๏ธ 72โ75ยฐF (narrow) |
| pH Range | 6.0โ7.5 | 8.1โ8.4 | โ No overlap |
| Temperament | peaceful | aggressive | โ Risk |
| Adult Size | 2.6 in | 15.0 in | โ 6ร difference |
| Min. Group | 4+ | 1+ | See below |
| Min. Tank Size | 100 gallons (for both species) | โ | |
Compatibility Positives
Incompatibility Reasons
Species Profiles
Hillstream Loach โ Sewellia lineolata
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.
โ Full Hillstream Loach care guide
Lionfish โ Pterois volitans
Lionfish are popular saltwater aquarium fish known for their striking colors and intimidating spines. These fish require a large tank and careful attention to water parameters. Aggressive by nature, they can be harmful to smaller fish and invertebrates.
Frequently Asked Questions
Can Hillstream Loach live with Lionfish?
Generally not recommended. Hillstream Loach and Lionfish are generally not recommended to be housed together. One of these is a marine species and the other is not; they cannot share one aquarium. The adult size gap creates a meaningful predation risk. Review the behavior and water details before deciding whether to attempt the pairing.
What tank size do I need for Hillstream Loach and Lionfish together?
A minimum of 100 gallons is recommended for keeping Hillstream Loach and Lionfish together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Hillstream Loach and Lionfish?
72โ75ยฐF (narrow) โ inside Hillstream Loach's 68โ75ยฐF and Lionfish's 72โ82ยฐF.
Is a Hillstream Loach aggressive toward a Lionfish?
The adult size gap creates a meaningful predation risk.
Related Compatibility Guides
Tank Size for Hillstream Loach and Lionfish
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 120 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 180 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 220 gal | Best when keeping larger schools or reducing territorial pressure. |