Can Harlequin Rasbora and Telmatochromis brichardi Live Together?

Harlequin Rasbora is a peaceful species (1/10), while Telmatochromis brichardi is moderately assertive (6/10). This notable difference means Telmatochromis brichardi may occasionally assert dominance over Harlequin Rasbora.

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

The safe temperature window for both species falls between 24°C and 28°C. Aim for the midpoint of this range (around 26.0°C) for optimal comfort.

The pH requirements of Harlequin Rasbora (5–7.5) and Telmatochromis brichardi (8–9.3) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–12 dGH. Regular testing will ensure conditions stay within this range.

To house Harlequin Rasbora and Telmatochromis brichardi together, plan for an aquarium of at least 75 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, Leaf Litter/Blackwater, Sand (Sifters), Shells (Breeding/Hiding), Established Algae (Otocinclus). 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.

Harlequin Rasbora and Telmatochromis brichardi 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.