Can Lyretail Killifish and Rummynose Rasbora Live Together?

Lyretail Killifish is a generally mild-mannered species (3/10), while Rummynose Rasbora is peaceful (2/10). This modest difference means Lyretail Killifish may occasionally assert dominance over Rummynose Rasbora.

Lyretail Killifish and Rummynose Rasbora 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: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Lyretail Killifish is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 21°C and 25°C. Aim for the midpoint of this range (around 23.0°C) for optimal comfort.

The pH requirements of Lyretail Killifish (5.5–7) and Rummynose Rasbora (7.3–8.5) 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 Lyretail Killifish and Rummynose Rasbora together, plan for an aquarium of at least 60 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: Plants - Densely covered, Plants - Floating, Leaf Litter/Blackwater. 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.

Lyretail Killifish and Rummynose Rasbora 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.