Can Apistogramma Marmor (Marbled Apisto) and Cuckoo Catfish Live Together?

Apistogramma Marmor (Marbled Apisto) is a generally mild-mannered species (4/10), while Cuckoo Catfish is moderately assertive (5/10). This modest difference means Cuckoo Catfish may occasionally assert dominance over Apistogramma Marmor (Marbled Apisto).

Apistogramma Marmor (Marbled Apisto) and Cuckoo Catfish 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: Cuckoo Catfish is nocturnal and will be most active after lights-out, naturally reducing daytime encounters.

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 Apistogramma Marmor (Marbled Apisto) (5.5–7) and Cuckoo Catfish (7.5–9) 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.

To house Apistogramma Marmor (Marbled Apisto) and Cuckoo Catfish together, plan for an aquarium of at least 340 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), Leaf Litter/Blackwater, Driftwood (Digestion/Hiding), 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.

Apistogramma Marmor (Marbled Apisto) and Cuckoo Catfish 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.