Can Common Whiptail Catfish and Moonlight Gourami Live Together?

Common Whiptail Catfish is a peaceful species (1/10), while Moonlight Gourami is generally mild-mannered (3/10). This modest difference means Moonlight Gourami may occasionally assert dominance over Common Whiptail Catfish.

In terms of spatial distribution, Common Whiptail Catfish prefers the Bottom (Substrate) zone, whereas Moonlight Gourami occupies the Top (Surface) 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: Common Whiptail Catfish is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Moonlight Gourami is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 25°C and 27°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 2–15 dGH. Regular testing will ensure conditions stay within this range.

To house Common Whiptail Catfish and Moonlight Gourami together, plan for an aquarium of at least 150 litres with a minimum length of 90 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, Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding), Plants - Densely covered, Plants - Floating. Meeting these requirements will help both species thrive.

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

Common Whiptail Catfish and Moonlight Gourami work best when the tank gives each fish enough room to use its preferred level of the aquarium and enough cover to avoid constant visual contact. The score matters, but the real-world success usually comes from matching their pace, keeping water stable, and resisting the urge to crowd the tank just because the pair looks safe on paper.