Can Black Ocellatus and Cigar Shark (Mad Barb) Live Together?

Black Ocellatus is a semi-aggressive species (7/10), while Cigar Shark (Mad Barb) is generally mild-mannered (4/10). This modest difference means Black Ocellatus may occasionally assert dominance over Cigar Shark (Mad Barb).

In terms of spatial distribution, Black Ocellatus prefers the Bottom (Substrate) zone, whereas Cigar Shark (Mad Barb) occupies the Middle (Open Water) and Top (Surface) zones. 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..

Worth noting: Cigar Shark (Mad Barb) is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 23°C and 28°C. Aim for the midpoint of this range (around 25.5°C) for optimal comfort.

Both fish can tolerate a pH between 7.5 and 8. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 8–15 dGH. Regular testing will ensure conditions stay within this range.

To house Black Ocellatus and Cigar Shark (Mad Barb) together, plan for an aquarium of at least 1000 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: Sand (Sifters), Shells (Breeding/Hiding), Smooth Gravel (Sensitive Barbels). Meeting these requirements will help both species thrive.

Black Ocellatus prefers Low (Still Water) flow while Cigar Shark (Mad Barb) needs High (River/Stream) flow. Consider positioning filter outlets and using baffles to create zones of different current intensity within the same tank.

Black Ocellatus and Cigar Shark (Mad Barb) 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.