Can Marbled Hatchetfish and Midnight Catfish Live Together?

Marbled Hatchetfish is a peaceful species (1/10), while Midnight Catfish is generally mild-mannered (3/10). This modest difference means Midnight Catfish may occasionally assert dominance over Marbled Hatchetfish.

In terms of spatial distribution, Marbled Hatchetfish prefers the Top (Surface) zone, whereas Midnight Catfish occupies the Bottom (Substrate) and Middle (Open Water) zones. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

Worth noting: Midnight Catfish is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Marbled Hatchetfish is a known jumper, so a tight-fitting lid is essential.

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.

Both fish can tolerate a pH between 6 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 2–12 dGH. Regular testing will ensure conditions stay within this range.

To house Marbled Hatchetfish and Midnight Catfish together, plan for an aquarium of at least 110 litres with a minimum length of 80 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: Plants - Floating, Leaf Litter/Blackwater, Driftwood (Digestion/Hiding), Plants - Densely covered. 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.