Can Arulius Barb and Reticulated Hillstream Loach Live Together?

Reviewed by Guidarium Editorial DeskUpdated April 29, 2026
Ideal Tank Mates

Yes, Arulius Barb and Reticulated Hillstream Loach are ideal tank mates. Both species share compatible water parameters and peaceful temperaments, making them well-suited for a community aquarium. A minimum tank size of 200 litres is recommended.


At a Glance

Arulius Barb

Dawkinsia arulius

Reticulated Hillstream Loach

Sewellia lineolata

🐠Family Group
Arulius Barb
Cyprinids
Reticulated Hillstream Loach
Loaches
Temperament
Arulius Barb
Mostly Peaceful (4/10)
Reticulated Hillstream Loach
Mostly Peaceful (3/10)
Temperature
✓ Compatible
Arulius Barb
19–25°C
Reticulated Hillstream Loach
20–24°C
pH Range
✓ Compatible
Arulius Barb
6–7.5
Reticulated Hillstream Loach
6.5–7.5
Hardness (dGH)
✓ Compatible
Arulius Barb
2–15
Reticulated Hillstream Loach
4–15
Water Type
✓ Compatible
Arulius Barb
Freshwater Only
Reticulated Hillstream Loach
Freshwater Only
Flow Preference
✓ Compatible
Arulius Barb
High
Reticulated Hillstream Loach
High
Min Tank Volume
Combined: 200 L
Arulius Barb
200 L
Reticulated Hillstream Loach
80 L
Swimming Level
Shared: 1 zone
Arulius Barb
MiddleBottom
Reticulated Hillstream Loach
Bottom
🏷️Behavior Tags
Arulius Barb
Hyperactive / Fast SwimmerJumper (Lid Required)Fin NipperAggressive Eater (Starves shy fish)
Reticulated Hillstream Loach
Hyperactive / Fast SwimmerTerritorial (Defends specific area)
Stocking calculator

Can your tank handle Arulius Barb and Reticulated Hillstream Loach?

Compatibility is only part of the answer. Test both fish with your real tank size, current stock, and maintenance needs to see if you have enough space and a safe stocking level before you add them.

Arulius Barb
Reticulated Hillstream Loach
Test both in my tank

Behaviour & Temperament

Arulius Barb is a generally mild-mannered species (4/10), while Reticulated Hillstream Loach is generally mild-mannered (3/10). This modest difference means Arulius Barb may occasionally assert dominance over Reticulated Hillstream Loach.

Arulius Barb and Reticulated Hillstream Loach both frequent the Bottom (Substrate) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Worth noting: Arulius Barb is a known jumper, so a tight-fitting lid is essential.

Water Parameters

The safe temperature window for both species falls between 20°C and 24°C. Aim for the midpoint of this range (around 22.0°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 4–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Arulius Barb and Reticulated Hillstream Loach together, plan for an aquarium of at least 200 litres with a minimum length of 120 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Providing a mix of open swimming space and sheltered areas with rocks, driftwood, or plants will keep both species comfortable and allow natural behaviour.

Specific environmental needs for this combination include: Smooth Gravel (Sensitive Barbels), Established Algae (Otocinclus), Plants - lighly covered. Meeting these requirements will help both species thrive.

Both species do well with high (river/stream) water movement, so a standard filtration setup rated for the tank volume should suffice.

Why This Pairing Works in Practice

Arulius Barb and Reticulated Hillstream Loach work best when the tank gives each fish enough room to use its preferred level of the aquarium and enough cover to avoid constant visual contact. The score matters, but the real-world success usually comes from matching their pace, keeping water stable, and resisting the urge to crowd the tank just because the pair looks safe on paper.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Arulius Barb and Reticulated Hillstream Loach.

Show 5 more tank sizes

Frequently Asked Questions

Can Arulius Barb and Reticulated Hillstream Loach live together?

Yes. Arulius Barb and Reticulated Hillstream Loach are considered ideal tank mates. Their water parameters, temperaments, and behaviour profiles are well matched for a community aquarium.

What size tank do Arulius Barb and Reticulated Hillstream Loach need?

A minimum of 200 litres (tank length at least 120 cm) is recommended. This provides enough space for both species to establish their own areas and reduces the likelihood of territorial disputes.

What water temperature is best for Arulius Barb and Reticulated Hillstream Loach together?

Keep the aquarium between 20°C and 24°C. A target of around 22.0°C sits comfortably within both species' preferred ranges.

Are Arulius Barb or Reticulated Hillstream Loach aggressive?

Arulius Barb is generally mild-mannered (4/10) and Reticulated Hillstream Loach is generally mild-mannered (3/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Arulius Barb and Reticulated Hillstream Loach need?

Both species overlap in the 6.5–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Will Arulius Barb nip Reticulated Hillstream Loach's fins?

Arulius Barb is a known fin nipper. If Reticulated Hillstream Loach has long or flowing fins, there is a real risk of fin damage. Keeping Arulius Barb in a larger group can help redirect nipping behaviour toward conspecifics.

How do I manage Reticulated Hillstream Loach's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Reticulated Hillstream Loach space to claim a territory without encroaching on the other fish's area. Adding décor that divides the tank into distinct zones works especially well.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
April 29, 2026
Last updated
April 29, 2026
Issues or corrections?
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