Can Cairns Rainbowfish and Reedfish (Ropefish) Live Together?

Cairns Rainbowfish is a peaceful species (2/10), while Reedfish (Ropefish) is generally mild-mannered (3/10). This modest difference means Reedfish (Ropefish) may occasionally assert dominance over Cairns Rainbowfish.

Cairns Rainbowfish and Reedfish (Ropefish) 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.

Worth noting: Reedfish (Ropefish) is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Cairns 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.

Both fish can tolerate a pH between 6.5 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–10 dGH. Regular testing will ensure conditions stay within this range.

To house Cairns Rainbowfish and Reedfish (Ropefish) together, plan for an aquarium of at least 180 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.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding), Leaf Litter/Blackwater, Sand (Sifters), Plants - Densely covered. Meeting these requirements will help both species thrive.

Cairns Rainbowfish prefers High (River/Stream) flow while Reedfish (Ropefish) needs Low (Still Water) flow. Consider positioning filter outlets and using baffles to create zones of different current intensity within the same tank.

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Cairns Rainbowfish and Reedfish (Ropefish) need extra room, more cover, and closer observation during the first few weeks so small aggression, feeding, or territory issues do not snowball into a long-term problem.