Can Cigar Shark (Mad Barb) and Marlier's Julie Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 6, 2026
Not Recommended

Cigar Shark (Mad Barb) and Marlier's Julie are not recommended as tank mates due to conflicting pH requirements. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Cigar Shark (Mad Barb)

Leptobarbus hoevenii

Marlier's Julie

Julidochromis marlieri

🐠Family Group
Cigar Shark (Mad Barb)
Cyprinids
Marlier's Julie
Cichlids - African
Temperament
Cigar Shark (Mad Barb)
Mostly Peaceful (4/10)
Marlier's Julie
Semi-Aggressive (6/10)
Temperature
✓ Compatible
Cigar Shark (Mad Barb)
23–28°C
Marlier's Julie
23–27°C
pH Range
✗ No overlap
Cigar Shark (Mad Barb)
6–8
Marlier's Julie
8.2–9.3
Hardness (dGH)
✓ Compatible
Cigar Shark (Mad Barb)
4–15
Marlier's Julie
10–25
Water Type
✓ Compatible
Cigar Shark (Mad Barb)
Freshwater Only
Marlier's Julie
Freshwater Only
Flow Preference
✓ Compatible
Cigar Shark (Mad Barb)
High
Marlier's Julie
Moderate
Min Tank Volume
Combined: 1000 L
Cigar Shark (Mad Barb)
1000 L
Marlier's Julie
114 L
Swimming Level
Shared: 1 zone
Cigar Shark (Mad Barb)
MiddleTop
Marlier's Julie
BottomMiddle
🏷️Behavior Tags
Cigar Shark (Mad Barb)
Hyperactive / Fast SwimmerJumper (Lid Required)Piscivore (Eats small/nano fish)Plant DestroyerAggressive Eater (Starves shy fish)
Marlier's Julie
Territorial (Defends specific area)Aggressive to same species/look-alikesDigger (Disturbs Substrate)Fry Predator
Stocking calculator

Can your tank handle Cigar Shark (Mad Barb) and Marlier's Julie?

Compatibility is only part of the answer. Test both fish with your real tank size, current stock, and maintenance needs to see if you have enough space and a safe stocking level before you add them.

Cigar Shark (Mad Barb)
Marlier's Julie
Test both in my tank

Behaviour & Temperament

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

Cigar Shark (Mad Barb) and Marlier's Julie both frequent the 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.

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

Water Parameters

The safe temperature window for both species falls between 23°C and 27°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

The pH requirements of Cigar Shark (Mad Barb) (6–8) and Marlier's Julie (8.2–9.3) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Cigar Shark (Mad Barb) and Marlier's Julie 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: Smooth Gravel (Sensitive Barbels), Sand (Sifters). Meeting these requirements will help both species thrive.

Both species do well with high (river/stream) water movement, so a standard filtration setup rated for the tank volume should suffice.

Why This Pairing Usually Fails in Practice

Cigar Shark (Mad Barb) and Marlier's Julie 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.

Frequently Asked Questions

Can Cigar Shark (Mad Barb) and Marlier's Julie live together?

No. This combination is not recommended. Key incompatibilities — such as critical behavioural conflicts — make cohabitation unsafe.

What size tank do Cigar Shark (Mad Barb) and Marlier's Julie need?

A minimum of 1000 litres (tank length at least 240 cm) is recommended. This provides enough space for both species to establish their own areas and reduces the likelihood of territorial disputes.

What water temperature is best for Cigar Shark (Mad Barb) and Marlier's Julie together?

Keep the aquarium between 23°C and 27°C. A target of around 25.0°C sits comfortably within both species' preferred ranges.

Are Cigar Shark (Mad Barb) or Marlier's Julie aggressive?

Cigar Shark (Mad Barb) is generally mild-mannered (4/10) and Marlier's Julie is moderately assertive (6/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Cigar Shark (Mad Barb) and Marlier's Julie need?

Their pH requirements do not overlap. Cigar Shark (Mad Barb) prefers 6–8, while Marlier's Julie needs 8.2–9.3. This makes them incompatible in the same water chemistry.

How do I manage Marlier's Julie's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Marlier's Julie space to claim a territory without encroaching on the other fish's area. Adding décor that divides the tank into distinct zones works especially well.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
May 6, 2026
Last updated
May 6, 2026
Issues or corrections?
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