Can Keyhole Cichlid and Red Empress Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Not Recommended

Keyhole Cichlid and Red Empress 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

Keyhole Cichlid

Cleithracara maronii

Red Empress

Protomelas taeniolatus

🐠Family Group
Keyhole Cichlid
Cichlids - South American
Red Empress
Cichlids - African
Temperament
Keyhole Cichlid
Peaceful (2/10)
Red Empress
Semi-Aggressive (6/10)
Temperature
✓ Compatible
Keyhole Cichlid
22–28°C
Red Empress
24–28°C
pH Range
✗ No overlap
Keyhole Cichlid
6–7.5
Red Empress
7.8–8.6
Hardness (dGH)
✓ Compatible
Keyhole Cichlid
2–15
Red Empress
10–25
Water Type
✓ Compatible
Keyhole Cichlid
Freshwater Only
Red Empress
Freshwater Only
Flow Preference
✓ Compatible
Keyhole Cichlid
Low
Red Empress
Moderate
Min Tank Volume
Combined: 280 L
Keyhole Cichlid
110 L
Red Empress
280 L
Swimming Level
Shared: 2 zones
Keyhole Cichlid
MiddleBottom
Red Empress
MiddleBottom
🏷️Behavior Tags
Keyhole Cichlid
Shy / Slow Moving (Easily Stressed)Fry Predator
Red Empress
Territorial (Defends specific area)Aggressive to same species/look-alikesHyperactive / Fast SwimmerDigger (Disturbs Substrate)
Stocking calculator

Can your tank handle Keyhole Cichlid and Red Empress?

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.

Keyhole Cichlid
Red Empress
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Behaviour & Temperament

Keyhole Cichlid is a peaceful species (2/10), while Red Empress is moderately assertive (6/10). This notable difference means Red Empress may occasionally assert dominance over Keyhole Cichlid.

Keyhole Cichlid and Red Empress 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.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Water Parameters

The safe temperature window for both species falls between 24°C and 28°C. Aim for the midpoint of this range (around 26.0°C) for optimal comfort.

The pH requirements of Keyhole Cichlid (6–7.5) and Red Empress (7.8–8.6) 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 Keyhole Cichlid and Red Empress 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: Driftwood (Digestion/Hiding), Plants - Densely covered, Leaf Litter/Blackwater, Sand (Sifters), Smooth Gravel (Sensitive Barbels). Meeting these requirements will help both species thrive.

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

Why This Pairing Usually Fails in Practice

Keyhole Cichlid and Red Empress 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 Keyhole Cichlid and Red Empress.

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Frequently Asked Questions

Can Keyhole Cichlid and Red Empress live together?

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

What size tank do Keyhole Cichlid and Red Empress 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 Keyhole Cichlid and Red Empress together?

Keep the aquarium between 24°C and 28°C. A target of around 26.0°C sits comfortably within both species' preferred ranges.

Are Keyhole Cichlid or Red Empress aggressive?

Keyhole Cichlid is peaceful (2/10) and Red Empress is moderately assertive (6/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Keyhole Cichlid and Red Empress need?

Their pH requirements do not overlap. Keyhole Cichlid prefers 6–7.5, while Red Empress needs 7.8–8.6. This makes them incompatible in the same water chemistry.

How do I manage Red Empress's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Red Empress 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
Issues or corrections?
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