Can Keyhole Cichlid and Scat (Brackish) Live Together?

🔴Not Recommended

Keyhole Cichlid and Scat (Brackish) are not recommended as tank mates due to incompatible water types. 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

Scat (Brackish)

Scatophagus argus

🐠Family Group
Keyhole Cichlid
Cichlids - South American
Scat (Brackish)
Oddballs
Temperament
Keyhole Cichlid
Peaceful (2/10)
Scat (Brackish)
Mostly Peaceful (4/10)
Temperature
✓ Compatible
Keyhole Cichlid
22–28°C
Scat (Brackish)
20–28°C
pH Range
✓ Compatible
Keyhole Cichlid
6–7.5
Scat (Brackish)
7.5–8.5
Hardness (dGH)
✓ Compatible
Keyhole Cichlid
2–15
Scat (Brackish)
12–30
Water Type
✗ No overlap
Keyhole Cichlid
Freshwater Only
Scat (Brackish)
Brackish Required
Flow Preference
✗ No overlap
Keyhole Cichlid
Low
Scat (Brackish)
High
Min Tank Volume
Combined: 540 L
Keyhole Cichlid
110 L
Scat (Brackish)
450 L
Swimming Level
Shared: 2 zones
Keyhole Cichlid
MiddleBottom
Scat (Brackish)
MiddleBottom
🏷️Behavior Tags
Keyhole Cichlid
Shy / Slow Moving (Easily Stressed)Fry Predator
Scat (Brackish)
Plant DestroyerHyperactive / Fast SwimmerAggressive Eater (Starves shy fish)Fin Nipper

Behaviour & Temperament

Keyhole Cichlid is a peaceful species (2/10), while Scat (Brackish) is generally mild-mannered (4/10). This modest difference means Scat (Brackish) may occasionally assert dominance over Keyhole Cichlid.

Keyhole Cichlid and Scat (Brackish) 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. Aggressive eaters may outcompete shy fish for food, leading to malnutrition.

Water Parameters

The safe temperature window for both species falls between 22°C and 28°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

Both fish can tolerate a pH between 7.5 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 12–15 dGH. Regular testing will ensure conditions stay within this range.

Crucially, these species require different water types — one needs freshwater while the other requires brackish conditions. This is a hard barrier to keeping them together. An aquarium test kit is recommended for monitoring.

Tank Setup

To house Keyhole Cichlid and Scat (Brackish) together, plan for an aquarium of at least 540 litres with a minimum length of 150 cm. This accounts for the larger species' space requirements with an additional 20 % buffer to reduce territorial tension.

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), Established Algae (Otocinclus). Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Scat (Brackish) is a plant destroyer, which conflicts with Keyhole Cichlid's requirement for live plants. Compromise where possible or prioritise the more critical need.

Keyhole Cichlid prefers Low (Still Water) flow while Scat (Brackish) needs High (River/Stream) flow. Consider positioning filter outlets and using baffles to create zones of different current intensity within the same tank.

Find the right tank equipment

Browse tanks, décor, and equipment suited for this setup.

Diet & Feeding

Feeding time deserves special attention with this pairing. Scat (Brackish) is an aggressive eater that may prevent Keyhole Cichlid from getting enough food.

Because Scat (Brackish) is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Keyhole Cichlid receives an adequate share.

Frequently Asked Questions

Can Keyhole Cichlid and Scat (Brackish) live together?

No. This combination is not recommended. Key incompatibilities — such as different water type needs — make cohabitation unsafe.

What size tank do Keyhole Cichlid and Scat (Brackish) need?

A minimum of 540 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 Keyhole Cichlid and Scat (Brackish) together?

Keep the aquarium between 22°C and 28°C. A target of around 25.0°C sits comfortably within both species' preferred ranges.

Are Keyhole Cichlid or Scat (Brackish) aggressive?

Keyhole Cichlid is peaceful (2/10) and Scat (Brackish) is generally mild-mannered (4/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Keyhole Cichlid and Scat (Brackish) need?

Both species overlap in the 7.5–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Will Scat (Brackish) nip Keyhole Cichlid's fins?

Scat (Brackish) is a known fin nipper. If Keyhole Cichlid has long or flowing fins, there is a real risk of fin damage. Keeping Scat (Brackish) in a larger group can help redirect nipping behaviour toward conspecifics.


Related Comparisons