Can Cigar Shark (Mad Barb) and Peacock Eel Live Together?

Cigar Shark (Mad Barb) is a generally mild-mannered species (4/10), while Peacock Eel is peaceful (2/10). This modest difference means Cigar Shark (Mad Barb) may occasionally assert dominance over Peacock Eel.

In terms of spatial distribution, Cigar Shark (Mad Barb) prefers the Middle (Open Water) and Top (Surface) zones, whereas Peacock Eel 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: Hyperactive swimmers can stress shy, slow-moving species through constant motion. Aggressive eaters may outcompete shy fish for food, leading to malnutrition.

Worth noting: Peacock Eel is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Cigar Shark (Mad Barb) is a known jumper, so a tight-fitting lid is essential.

To improve the chances of a peaceful coexistence in this community tank: 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 28°C. Aim for the midpoint of this range (around 25.5°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 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 5–15 dGH. Regular testing will ensure conditions stay within this range.

To house Cigar Shark (Mad Barb) and Peacock Eel 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: Smooth Gravel (Sensitive Barbels), Sand (Sifters), Plants - Densely covered. Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Cigar Shark (Mad Barb) is a plant destroyer, which conflicts with Peacock Eel's requirement for live plants. Compromise where possible or prioritise the more critical need.

Cigar Shark (Mad Barb) prefers High (River/Stream) flow while Peacock Eel needs Low (Still Water) 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. Cigar Shark (Mad Barb) and Peacock Eel 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 Peacock Eel 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 Peacock Eel receives an adequate share.