Can Apistogramma baenschi (Inca 50) and Highlands Rainbowfish Live Together?

Apistogramma baenschi (Inca 50) is a moderately assertive species (5/10), while Highlands Rainbowfish is peaceful (2/10). This modest difference means Apistogramma baenschi (Inca 50) may occasionally assert dominance over Highlands Rainbowfish.

In terms of spatial distribution, Apistogramma baenschi (Inca 50) prefers the Bottom (Substrate) zone, whereas Highlands Rainbowfish occupies the Top (Surface) and Middle (Open Water) zones. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Highlands Rainbowfish is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 22°C and 26°C. Aim for the midpoint of this range (around 24.0°C) for optimal comfort.

The pH requirements of Apistogramma baenschi (Inca 50) (4–6.5) and Highlands Rainbowfish (7–7.8) 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 Apistogramma baenschi (Inca 50) and Highlands Rainbowfish together, plan for an aquarium of at least 110 litres with a minimum length of 90 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), Plants - Densely covered. 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 Highlands Rainbowfish 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.