Can Reticulated Hillstream Loach and Weeksi Bichir Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Possible with Caution

Keeping Reticulated Hillstream Loach and Weeksi Bichir together is possible but requires caution due to mismatched flow preferences. Provide a spacious tank of at least 470 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Reticulated Hillstream Loach

Sewellia lineolata

Weeksi Bichir

Polypterus weeksii

🐠Family Group
Reticulated Hillstream Loach
Loaches
Weeksi Bichir
Oddballs
Temperament
Reticulated Hillstream Loach
Mostly Peaceful (3/10)
Weeksi Bichir
Semi-Aggressive (6/10)
Temperature
✓ Compatible
Reticulated Hillstream Loach
20–24°C
Weeksi Bichir
24–28°C
pH Range
✓ Compatible
Reticulated Hillstream Loach
6.5–7.5
Weeksi Bichir
6–7.5
Hardness (dGH)
✓ Compatible
Reticulated Hillstream Loach
4–15
Weeksi Bichir
5–15
Water Type
✓ Compatible
Reticulated Hillstream Loach
Freshwater Only
Weeksi Bichir
Freshwater Only
Flow Preference
✗ No overlap
Reticulated Hillstream Loach
High
Weeksi Bichir
Low
Min Tank Volume
Combined: 470 L
Reticulated Hillstream Loach
80 L
Weeksi Bichir
470 L
Swimming Level
Shared: 1 zone
Reticulated Hillstream Loach
Bottom
Weeksi Bichir
Bottom
🏷️Behavior Tags
Reticulated Hillstream Loach
Hyperactive / Fast SwimmerTerritorial (Defends specific area)
Weeksi Bichir
Piscivore (Eats small/nano fish)NocturnalJumper (Lid Required)Shrimp EaterFry Predator
Stocking calculator

Can your tank handle Reticulated Hillstream Loach and Weeksi Bichir?

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.

Reticulated Hillstream Loach
Weeksi Bichir
Test both in my tank

Behaviour & Temperament

Reticulated Hillstream Loach is a generally mild-mannered species (3/10), while Weeksi Bichir is moderately assertive (6/10). This modest difference means Weeksi Bichir may occasionally assert dominance over Reticulated Hillstream Loach.

Reticulated Hillstream Loach and Weeksi Bichir 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: Weeksi Bichir is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Weeksi Bichir is a known jumper, so a tight-fitting lid is essential.

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Reticulated Hillstream Loach and Weeksi Bichir to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations.

Water Parameters

The safe temperature window for both species falls between 24°C and 24°C. Aim for the midpoint of this range (around 24.0°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 5–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Reticulated Hillstream Loach and Weeksi Bichir together, plan for an aquarium of at least 470 litres with a minimum length of 150 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Smooth Gravel (Sensitive Barbels), Established Algae (Otocinclus), Plants - lighly covered, Sand (Sifters), Driftwood (Digestion/Hiding), Leaf Litter/Blackwater. Meeting these requirements will help both species thrive.

Reticulated Hillstream Loach prefers High (River/Stream) flow while Weeksi Bichir needs Low (Still Water) flow. Consider positioning filter outlets and using baffles to create zones of different current intensity within the same tank.

Why This Pairing Needs Extra Planning in Practice

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Reticulated Hillstream Loach and Weeksi Bichir need extra room, more cover, and closer observation during the first few weeks so small aggression, feeding, or territory issues do not snowball into a long-term problem.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Reticulated Hillstream Loach and Weeksi Bichir.

Frequently Asked Questions

Can Reticulated Hillstream Loach and Weeksi Bichir live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 470 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Reticulated Hillstream Loach and Weeksi Bichir need?

A minimum of 470 litres (tank length at least 150 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 Reticulated Hillstream Loach and Weeksi Bichir together?

Keep the aquarium between 24°C and 24°C. A target of around 24.0°C sits comfortably within both species' preferred ranges.

Are Reticulated Hillstream Loach or Weeksi Bichir aggressive?

Reticulated Hillstream Loach is generally mild-mannered (3/10) and Weeksi Bichir is moderately assertive (6/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Reticulated Hillstream Loach and Weeksi Bichir 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.

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.

Does Weeksi Bichir being nocturnal affect compatibility?

Weeksi Bichir is most active after lights-out, which naturally reduces daytime encounters with its tank mate. This can actually be beneficial, as both fish get undisturbed time to feed and explore. Just ensure food reaches Weeksi Bichir during evening hours.

Editorial Review

Guidarium Editorial Desk

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

Last reviewed
May 11, 2026
Last updated
May 11, 2026
Issues or corrections?
Contact the editorial team

Related Comparisons

Reticulated Hillstream Loach & Hillstream Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulHillstream Loach: Peaceful

Reticulated Hillstream Loach & Mottled Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulMottled Loach: Peaceful

Reticulated Hillstream Loach & Phuket Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulPhuket Loach: Peaceful

Reticulated Hillstream Loach & Spotted Hillstream Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulSpotted Hillstream Loach: Peaceful

Reticulated Hillstream Loach & Angelicus Botia

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulAngelicus Botia: Peaceful

Reticulated Hillstream Loach & Banana Loach

·

Possible with Caution
Reticulated Hillstream Loach: PeacefulBanana Loach: Peaceful

Weeksi Bichir & African Knifefish

·

Possible with Caution
Weeksi Bichir: PeacefulAfrican Knifefish: Peaceful

Weeksi Bichir & Buettikoferi Bichir

·

Possible with Caution
Weeksi Bichir: PeacefulBuettikoferi Bichir: Peaceful

Weeksi Bichir & Delhezi Bichir (Armored Bichir)

·

Possible with Caution
Weeksi Bichir: PeacefulDelhezi Bichir (Armored Bichir): Peaceful

Weeksi Bichir & Freshwater Toadfish (Prehistoric Monster Fish)

·

Possible with Caution
Weeksi Bichir: PeacefulFreshwater Toadfish (Prehistoric Monster Fish): Peaceful

Weeksi Bichir & Guinean Bichir

·

Possible with Caution
Weeksi Bichir: PeacefulGuinean Bichir: Peaceful

Weeksi Bichir & Marbled Bichir

·

Possible with Caution
Weeksi Bichir: PeacefulMarbled Bichir: Peaceful