Can Horei Cichlid and Zebra Oto Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Not Recommended

Horei Cichlid and Zebra Oto are not recommended as tank mates due to conflicting pH requirements and piscivorous fish will prey on nano-sized tank mates.. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Horei Cichlid

Ctenochromis horei

Zebra Oto

Otocinclus cocama

🐠Family Group
Horei Cichlid
Cichlids - African
Zebra Oto
Catfish
Temperament
Horei Cichlid
Aggressive (8/10)
Zebra Oto
Peaceful (0/10)
Temperature
✓ Compatible
Horei Cichlid
24–28°C
Zebra Oto
21–26°C
pH Range
✗ No overlap
Horei Cichlid
7.8–9
Zebra Oto
6–7.5
Hardness (dGH)
✓ Compatible
Horei Cichlid
10–25
Zebra Oto
2–10
Water Type
✓ Compatible
Horei Cichlid
Freshwater Only
Zebra Oto
Freshwater Only
Flow Preference
✓ Compatible
Horei Cichlid
Moderate
Zebra Oto
Moderate
Min Tank Volume
Combined: 208 L
Horei Cichlid
208 L
Zebra Oto
40 L
Swimming Level
Shared: 2 zones
Horei Cichlid
MiddleBottom
Zebra Oto
MiddleBottom
🏷️Behavior Tags
Horei Cichlid
Territorial (Defends specific area)Generally AggressiveAggressive to same species/look-alikesPiscivore (Eats small/nano fish)Digger (Disturbs Substrate)Fry Predator
Zebra Oto
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)
Stocking calculator

Can your tank handle Horei Cichlid and Zebra Oto?

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.

Horei Cichlid
Zebra Oto
Test both in my tank

Behaviour & Temperament

Horei Cichlid is a semi-aggressive species (8/10), while Zebra Oto is peaceful (0/10). This notable difference means Horei Cichlid may occasionally assert dominance over Zebra Oto.

Large aggression gap (8 points) between Horei Cichlid and Zebra Oto increases stress risk for the more peaceful fish.

Horei Cichlid and Zebra Oto both frequent the Middle (Open Water) and 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.

There is a critical concern: the Piscivore (Eats small/nano fish) behaviour of one fish directly conflicts with the Nano / Bite-sized (Predation Risk) trait of the other — piscivorous fish will prey on nano-sized tank mates..

Additional behavioural considerations to keep in mind: Aggressive fish may bully and stress shy, slow-moving species.

Water Parameters

The safe temperature window for both species falls between 24°C and 26°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

The pH requirements of Horei Cichlid (7.8–9) and Zebra Oto (6–7.5) do not overlap, making it impossible to satisfy both species simultaneously.

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

Tank Setup

To house Horei Cichlid and Zebra Oto together, plan for an aquarium of at least 208 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), Established Algae (Otocinclus), Driftwood (Digestion/Hiding), Plants - Densely covered. Meeting these requirements will help both species thrive.

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

Why This Pairing Usually Fails in Practice

Horei Cichlid and Zebra Oto 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 Horei Cichlid and Zebra Oto.

Show 5 more tank sizes

Frequently Asked Questions

Can Horei Cichlid and Zebra Oto live together?

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

What size tank do Horei Cichlid and Zebra Oto need?

A minimum of 208 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 Horei Cichlid and Zebra Oto together?

Keep the aquarium between 24°C and 26°C. A target of around 25.0°C sits comfortably within both species' preferred ranges.

Are Horei Cichlid or Zebra Oto aggressive?

Horei Cichlid is semi-aggressive (8/10) and Zebra Oto is peaceful (0/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Horei Cichlid and Zebra Oto need?

Their pH requirements do not overlap. Horei Cichlid prefers 7.8–9, while Zebra Oto needs 6–7.5. This makes them incompatible in the same water chemistry.

How do I manage Horei Cichlid's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Horei Cichlid 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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