Can Chocolate Gourami and Least Killifish (Heterandria) Live Together?

Chocolate Gourami is a peaceful species (2/10), while Least Killifish (Heterandria) is peaceful (1/10). This modest difference means Chocolate Gourami may occasionally assert dominance over Least Killifish (Heterandria).

Chocolate Gourami and Least Killifish (Heterandria) both frequent the Top (Surface), 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.

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.

The pH requirements of Chocolate Gourami (4–6.5) and Least Killifish (Heterandria) (7–8) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 5–5 dGH. Regular testing will ensure conditions stay within this range.

To house Chocolate Gourami and Least Killifish (Heterandria) together, plan for an aquarium of at least 55 litres with a minimum length of 60 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, Plants - Densely covered, Plants - Floating, Driftwood (Digestion/Hiding). 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.