Loach | Hillstream Loach (Sewellia lineolata)

Loach | Hillstream Loach (Sewellia lineolata)

The Hillstream Loach, scientifically known as Sewellia lineolata, is a fascinating freshwater fish adapted to fast-moving, oxygen-rich streams. With its flattened body and suction-cup fins, this loach clings effortlessly to rocks and glass while grazing on biofilm and algae.

Often compared to a freshwater “stingray” in appearance, Hillstream Loaches are peaceful, active, and best kept in well-oxygenated river-style aquariums. Their striking patterns and unusual swimming style make them a standout addition for experienced aquarists.

Key Characteristics

✔ Unique flattened, ray-like body shape
✔ Excellent biofilm & algae grazer
✔ Peaceful temperament
✔ Thrives in high-flow, oxygen-rich tanks
✔ Fascinating natural behavior

Care Requirements

• Difficulty: Moderate
• Temperament: Peaceful
• Adult Size: ~2.5–3 inches
• Tank Size: 20 gallons or larger
• Temperature: 68–75°F
• pH: 6.5–7.5
• Diet: Omnivore (algae, biofilm, sinking wafers, frozen foods)

🌊 Strong water flow and high oxygen levels are essential.

Tank Setup Recommendations

• River-style aquascape
• Smooth rocks & rounded stones
• Strong filtration and powerheads
• Sand or fine gravel substrate
• Cool, well-oxygenated water

Tank Compatibility

Good Tankmates:

• Danios
• White cloud minnows
• Other hillstream loaches
• Peaceful, current-loving fish

Avoid:

• Warm-water species
• Slow or aggressive fish
• Poorly oxygenated tanks

👥 Best kept in small groups (3–5+) when space allows.

Ideal For

• River-style aquariums
• High-flow freshwater tanks
• Algae control with personality
• Experienced aquarists
• Unique bottom-dwelling fish displays

Product Details

• Common Name: Hillstream Loach
• Scientific Name: Sewellia lineolata
• Origin: Southeast Asia
• Aquarium Type: Freshwater
• Diet: Omnivore
• Temperament: Peaceful

FAQs – Hillstream Loach

Q: Are Hillstream Loaches good algae eaters?
A: Yes, especially for biofilm and soft algae.

Q: Can they live in warm tropical tanks?
A: No. They prefer cooler, fast-flowing water.

Q: Do they need strong current?
A: Yes. Strong flow and oxygenation are critical.

Q: Are they beginner-friendly?
A: Best for intermediate aquarists due to specific needs.

Q: Can they be kept alone?
A: They do best in small groups.