Can Threadfin Rainbowfish and Zebra Shovelnose (Tigrinus Catfish) Live Together?

Threadfin Rainbowfish is a peaceful species (1/10), while Zebra Shovelnose (Tigrinus Catfish) is generally mild-mannered (4/10). This modest difference means Zebra Shovelnose (Tigrinus Catfish) may occasionally assert dominance over Threadfin Rainbowfish.

In terms of spatial distribution, Threadfin Rainbowfish prefers the Top (Surface) and Middle (Open Water) zones, whereas Zebra Shovelnose (Tigrinus Catfish) 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.

There is a critical concern: the Nano / Bite-sized (Predation Risk) behaviour of one fish directly conflicts with the Piscivore (Eats small/nano fish) trait of the other — piscivorous fish will prey on nano-sized tank mates..

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

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

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.

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 2–12 dGH. Regular testing will ensure conditions stay within this range.

To house Threadfin Rainbowfish and Zebra Shovelnose (Tigrinus Catfish) together, plan for an aquarium of at least 1135 litres with a minimum length of 240 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, Plants - Floating, Sand (Sifters), Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding). Meeting these requirements will help both species thrive.

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

Threadfin Rainbowfish and Zebra Shovelnose (Tigrinus Catfish) 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.