Can Cardinal Tetra and Demasoni Cichlid (Mbuna) Live Together?

Cardinal Tetra is a peaceful species (1/10), while Demasoni Cichlid (Mbuna) is highly aggressive (9/10). This notable difference means Demasoni Cichlid (Mbuna) may occasionally assert dominance over Cardinal Tetra.

Large aggression gap (8 points) between Cardinal Tetra and Demasoni Cichlid (Mbuna) increases stress risk for the more peaceful fish.

Cardinal Tetra and Demasoni Cichlid (Mbuna) both frequent the Middle (Open Water) 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: Aggressive fish may bully and stress shy, slow-moving species. Hyperactive swimmers can stress shy, slow-moving species through constant motion.

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 Cardinal Tetra (4–7) and Demasoni Cichlid (Mbuna) (7.6–8.6) do not overlap, making it impossible to satisfy both species simultaneously.

Hardness requirements are incompatible: Cardinal Tetra needs 1–8 dGH while Demasoni Cichlid (Mbuna) requires 10–25 dGH.

To house Cardinal Tetra and Demasoni Cichlid (Mbuna) together, plan for an aquarium of at least 200 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: Leaf Litter/Blackwater, Driftwood (Digestion/Hiding), Plants - Densely covered, Sand (Sifters), Established Algae (Otocinclus). Meeting these requirements will help both species thrive.

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

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

Cardinal Tetra and Demasoni Cichlid (Mbuna) 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.