Can Apistogramma baenschi (Inca 50) and Longear Sunfish Live Together?

Apistogramma baenschi (Inca 50) is a moderately assertive species (5/10), while Longear Sunfish is semi-aggressive (7/10). This modest difference means Longear Sunfish may occasionally assert dominance over Apistogramma baenschi (Inca 50).

Apistogramma baenschi (Inca 50) and Longear Sunfish 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.

Additional behavioural considerations to keep in mind: Aggressive fish may bully and stress shy, slow-moving species. Two territorial species may clash over territory, especially in smaller tanks.

The safe temperature window for both species falls between 22°C and 25°C. Aim for the midpoint of this range (around 23.5°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 and 6.5. Maintaining a stable value within this band is more important than hitting an exact number.

Hardness requirements are incompatible: Apistogramma baenschi (Inca 50) needs 1–5 dGH while Longear Sunfish requires 8–20 dGH.

To house Apistogramma baenschi (Inca 50) and Longear Sunfish together, plan for an aquarium of at least 208 litres with a minimum length of 120 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, Driftwood (Digestion/Hiding), Smooth Gravel (Sensitive Barbels). 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.

Apistogramma baenschi (Inca 50) and Longear Sunfish 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.