Can Australian Pearl Arowana and Giant Whiptail Catfish Live Together?

Australian Pearl Arowana is a highly aggressive species (9/10), while Giant Whiptail Catfish is peaceful (2/10). This notable difference means Australian Pearl Arowana may occasionally assert dominance over Giant Whiptail Catfish.

Large aggression gap (7 points) between Australian Pearl Arowana and Giant Whiptail Catfish increases stress risk for the more peaceful fish.

In terms of spatial distribution, Australian Pearl Arowana prefers the Top (Surface) zone, whereas Giant Whiptail 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.

Additional behavioural considerations to keep in mind: Aggressive fish may bully and stress shy, slow-moving species.

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

There is no temperature overlap between Australian Pearl Arowana (24–30°C) and Giant Whiptail Catfish (16–23°C). This fundamental mismatch makes long-term cohabitation impractical.

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 4–15 dGH. Regular testing will ensure conditions stay within this range.

To house Australian Pearl Arowana and Giant Whiptail Catfish together, plan for an aquarium of at least 800 litres with a minimum length of 200 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: Smooth Gravel (Sensitive Barbels), Sand (Sifters), 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.

Australian Pearl Arowana and Giant Whiptail 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.