Can Reedfish (Ropefish) and Sumo Loach Live Together?

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

Keeping Reedfish (Ropefish) and Sumo Loach together is possible but requires caution due to differing aggression levels and mismatched flow preferences. Provide a spacious tank of at least 180 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Reedfish (Ropefish)

Erpetoichthys calabaricus

Sumo Loach

Schistura balteata

🐠Family Group
Reedfish (Ropefish)
Oddballs
Sumo Loach
Loaches
Temperament
Reedfish (Ropefish)
Mostly Peaceful (3/10)
Sumo Loach
Aggressive (7/10)
Temperature
✓ Compatible
Reedfish (Ropefish)
22–28°C
Sumo Loach
22–26°C
pH Range
✓ Compatible
Reedfish (Ropefish)
6–7.5
Sumo Loach
6.5–7.5
Hardness (dGH)
✓ Compatible
Reedfish (Ropefish)
5–20
Sumo Loach
2–12
Water Type
✓ Compatible
Reedfish (Ropefish)
Freshwater Only
Sumo Loach
Freshwater Only
Flow Preference
✗ No overlap
Reedfish (Ropefish)
Low
Sumo Loach
High
Min Tank Volume
Combined: 180 L
Reedfish (Ropefish)
180 L
Sumo Loach
100 L
Swimming Level
Shared: 1 zone
Reedfish (Ropefish)
BottomMiddle
Sumo Loach
Bottom
🏷️Behavior Tags
Reedfish (Ropefish)
Piscivore (Eats small/nano fish)Shrimp EaterJumper (Lid Required)NocturnalHyperactive / Fast SwimmerSlime Coat Eater (Attacks Flat Fish)
Sumo Loach
Aggressive to same species/look-alikesTerritorial (Defends specific area)Fin NipperShrimp EaterDigger (Disturbs Substrate)
Stocking calculator

Can your tank handle Reedfish (Ropefish) and Sumo 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.

Reedfish (Ropefish)
Sumo Loach
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Behaviour & Temperament

Reedfish (Ropefish) is a generally mild-mannered species (3/10), while Sumo Loach is semi-aggressive (7/10). This notable difference means Sumo Loach may occasionally assert dominance over Reedfish (Ropefish).

Reedfish (Ropefish) and Sumo 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: Reedfish (Ropefish) is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Reedfish (Ropefish) 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 Reedfish (Ropefish) and Sumo Loach to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations. A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat. Keep fin nippers in larger groups to distribute nipping behaviour among conspecifics rather than tank mates.

Water Parameters

The safe temperature window for both species falls between 22°C and 26°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 5–12 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Reedfish (Ropefish) and Sumo Loach together, plan for an aquarium of at least 180 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.

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: Sand (Sifters), Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding), Plants - Densely covered. Meeting these requirements will help both species thrive.

Reedfish (Ropefish) prefers Low (Still Water) flow while Sumo Loach needs High (River/Stream) 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. Reedfish (Ropefish) and Sumo Loach 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 Reedfish (Ropefish) and Sumo Loach.

Show 5 more tank sizes

Frequently Asked Questions

Can Reedfish (Ropefish) and Sumo Loach live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 180 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Reedfish (Ropefish) and Sumo Loach need?

A minimum of 180 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 Reedfish (Ropefish) and Sumo Loach together?

Keep the aquarium between 22°C and 26°C. A target of around 24.0°C sits comfortably within both species' preferred ranges.

Are Reedfish (Ropefish) or Sumo Loach aggressive?

Reedfish (Ropefish) is generally mild-mannered (3/10) and Sumo Loach is semi-aggressive (7/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Reedfish (Ropefish) and Sumo 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 Sumo Loach nip Reedfish (Ropefish)'s fins?

Sumo Loach is a known fin nipper. If Reedfish (Ropefish) has long or flowing fins, there is a real risk of fin damage. Keeping Sumo Loach in a larger group can help redirect nipping behaviour toward conspecifics.

How do I manage Sumo Loach's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Sumo 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 Reedfish (Ropefish) being nocturnal affect compatibility?

Reedfish (Ropefish) 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 Reedfish (Ropefish) 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
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