Can Harlequin Shark and Xenotilapia ochrogenys Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Not Recommended

Harlequin Shark and Xenotilapia ochrogenys are not recommended as tank mates due to conflicting pH requirements. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Harlequin Shark

Labeo variegatus

Xenotilapia ochrogenys

Xenotilapia ochrogenys

🐠Family Group
Harlequin Shark
Cyprinids
Xenotilapia ochrogenys
Cichlids - African
Temperament
Harlequin Shark
Aggressive (8/10)
Xenotilapia ochrogenys
Mostly Peaceful (4/10)
Temperature
✓ Compatible
Harlequin Shark
21–27°C
Xenotilapia ochrogenys
24–28°C
pH Range
✗ No overlap
Harlequin Shark
6–7.5
Xenotilapia ochrogenys
8–9
Hardness (dGH)
✓ Compatible
Harlequin Shark
3–15
Xenotilapia ochrogenys
10–25
Water Type
✓ Compatible
Harlequin Shark
Freshwater Only
Xenotilapia ochrogenys
Freshwater Only
Flow Preference
✓ Compatible
Harlequin Shark
High
Xenotilapia ochrogenys
Moderate
Min Tank Volume
Combined: 280 L
Harlequin Shark
150 L
Xenotilapia ochrogenys
200 L
Swimming Level
Shared: 1 zone
Harlequin Shark
Bottom
Xenotilapia ochrogenys
Bottom
🏷️Behavior Tags
Harlequin Shark
Generally AggressiveAggressive to same species/look-alikesTerritorial (Defends specific area)Hyperactive / Fast Swimmer
Xenotilapia ochrogenys
Digger (Disturbs Substrate)Jumper (Lid Required)Fry PredatorHyperactive / Fast Swimmer
Stocking calculator

Can your tank handle Harlequin Shark and Xenotilapia ochrogenys?

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.

Harlequin Shark
Xenotilapia ochrogenys
Test both in my tank

Behaviour & Temperament

Harlequin Shark is a semi-aggressive species (8/10), while Xenotilapia ochrogenys is generally mild-mannered (4/10). This notable difference means Harlequin Shark may occasionally assert dominance over Xenotilapia ochrogenys.

Harlequin Shark and Xenotilapia ochrogenys 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: Xenotilapia ochrogenys is a known jumper, so a tight-fitting lid is essential.

Water Parameters

The safe temperature window for both species falls between 24°C and 27°C. Aim for the midpoint of this range (around 25.5°C) for optimal comfort.

The pH requirements of Harlequin Shark (6–7.5) and Xenotilapia ochrogenys (8–9) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Harlequin Shark and Xenotilapia ochrogenys together, plan for an aquarium of at least 280 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: Sand (Sifters), Driftwood (Digestion/Hiding), Established Algae (Otocinclus), Smooth Gravel (Sensitive Barbels). 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 Usually Fails in Practice

Harlequin Shark and Xenotilapia ochrogenys are the kind of pair that can look acceptable in a shop but become a maintenance problem at home. The main risk is not a single number in the chart; it is the way incompatible behavior, water needs, or pressure on space compounds over time once both fish are established in the same tank.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Harlequin Shark and Xenotilapia ochrogenys.

Show 1 more tank size

Frequently Asked Questions

Can Harlequin Shark and Xenotilapia ochrogenys live together?

No. This combination is not recommended. Key incompatibilities — such as critical behavioural conflicts — make cohabitation unsafe.

What size tank do Harlequin Shark and Xenotilapia ochrogenys need?

A minimum of 280 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 Harlequin Shark and Xenotilapia ochrogenys together?

Keep the aquarium between 24°C and 27°C. A target of around 25.5°C sits comfortably within both species' preferred ranges.

Are Harlequin Shark or Xenotilapia ochrogenys aggressive?

Harlequin Shark is semi-aggressive (8/10) and Xenotilapia ochrogenys is generally mild-mannered (4/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Harlequin Shark and Xenotilapia ochrogenys need?

Their pH requirements do not overlap. Harlequin Shark prefers 6–7.5, while Xenotilapia ochrogenys needs 8–9. This makes them incompatible in the same water chemistry.

How do I manage Harlequin Shark's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Harlequin Shark 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
May 11, 2026
Last updated
May 11, 2026
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