Can Frontosa and Lyretail Killifish Live Together?

Frontosa is a moderately assertive species (5/10), while Lyretail Killifish is generally mild-mannered (3/10). This modest difference means Frontosa may occasionally assert dominance over Lyretail Killifish.

Frontosa and Lyretail Killifish 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.

There is a critical concern: the Piscivore (Eats small/nano fish) behaviour of one fish directly conflicts with the Nano / Bite-sized (Predation Risk) trait of the other — piscivorous fish will prey on nano-sized tank mates..

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

The safe temperature window for both species falls between 23°C and 26°C. Aim for the midpoint of this range (around 24.5°C) for optimal comfort.

The pH requirements of Frontosa (8–9) and Lyretail Killifish (5.5–7) do not overlap, making it impossible to satisfy both species simultaneously.

Hardness requirements are incompatible: Frontosa needs 12–25 dGH while Lyretail Killifish requires 1–10 dGH.

To house Frontosa and Lyretail Killifish together, plan for an aquarium of at least 570 litres with a minimum length of 180 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), Smooth Gravel (Sensitive Barbels), Plants - Densely covered, Plants - Floating, Leaf Litter/Blackwater. 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.

Frontosa and Lyretail Killifish 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.