Can Betta Macrostoma and Cigar Shark (Mad Barb) Live Together?

Betta Macrostoma is a moderately assertive species (6/10), while Cigar Shark (Mad Barb) is generally mild-mannered (4/10). This modest difference means Betta Macrostoma may occasionally assert dominance over Cigar Shark (Mad Barb).

Betta Macrostoma and Cigar Shark (Mad Barb) both frequent the Top (Surface) and 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.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion. Aggressive eaters may outcompete shy fish for food, leading to malnutrition.

Worth noting: Betta Macrostoma is a known jumper, so a tight-fitting lid is essential.

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Betta Macrostoma and Cigar Shark (Mad Barb) to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations. A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat.

The safe temperature window for both species falls between 23°C and 25°C. Aim for the midpoint of this range (around 24.0°C) for optimal comfort.

Both fish can tolerate a pH between 6 and 6. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 4–5 dGH. Regular testing will ensure conditions stay within this range.

To house Betta Macrostoma 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.

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: Leaf Litter/Blackwater, Driftwood (Digestion/Hiding), Plants - Floating, Smooth Gravel (Sensitive Barbels). Meeting these requirements will help both species thrive.

Betta Macrostoma 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.

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Betta Macrostoma and Cigar Shark (Mad Barb) 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.

Feeding time deserves special attention with this pairing. Cigar Shark (Mad Barb) is an aggressive eater that may prevent Betta Macrostoma from getting enough food.

Because Cigar Shark (Mad Barb) is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Betta Macrostoma receives an adequate share.