Can Giant Whiptail Catfish and Reedfish (Ropefish) Live Together?

Giant Whiptail Catfish 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 Giant Whiptail Catfish.

Giant Whiptail Catfish and Reedfish (Ropefish) 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.

There is a critical concern: the Shy / Slow Moving (Easily Stressed) behaviour of one fish directly conflicts with the Slime Coat Eater (Attacks Flat Fish) trait of the other — slime coat eaters target slow-moving fish, causing severe stress and health issues..

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

Worth noting: Giant Whiptail Catfish is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Reedfish (Ropefish) is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 22°C and 23°C. Aim for the midpoint of this range (around 22.5°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 5–15 dGH. Regular testing will ensure conditions stay within this range.

To house Giant Whiptail Catfish and Reedfish (Ropefish) together, plan for an aquarium of at least 400 litres with a minimum length of 150 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), Smooth Gravel (Sensitive Barbels), Established Algae (Otocinclus), Driftwood (Digestion/Hiding), Plants - Densely covered. Meeting these requirements will help both species thrive.

Giant Whiptail Catfish 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.

Giant Whiptail Catfish and Reedfish (Ropefish) 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.