Can Sailfin Molly and Two-spot Apistogramma Live Together?

Sailfin Molly is a generally mild-mannered species (3/10), while Two-spot Apistogramma is moderately assertive (5/10). This modest difference means Two-spot Apistogramma may occasionally assert dominance over Sailfin Molly.

Sailfin Molly and Two-spot Apistogramma both frequent the 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 22°C and 28°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

The pH requirements of Sailfin Molly (7.5–8.5) and Two-spot Apistogramma (5–7) do not overlap, making it impossible to satisfy both species simultaneously.

Hardness requirements are incompatible: Sailfin Molly needs 15–30 dGH while Two-spot Apistogramma requires 1–10 dGH.

To house Sailfin Molly and Two-spot Apistogramma 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: Established Algae (Otocinclus), Plants - Densely covered, Sand (Sifters), Leaf Litter/Blackwater, Driftwood (Digestion/Hiding). 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.

Sailfin Molly and Two-spot Apistogramma 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.