Can Regan's Julie and Sixbar Distichodus Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Not Recommended

Regan's Julie and Sixbar Distichodus 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

Regan's Julie

Julidochromis regani

Sixbar Distichodus

Distichodus sexfasciatus

🐠Family Group
Regan's Julie
Cichlids - African
Sixbar Distichodus
Characins
Temperament
Regan's Julie
Aggressive (7/10)
Sixbar Distichodus
Aggressive (7/10)
Temperature
✓ Compatible
Regan's Julie
23–27°C
Sixbar Distichodus
22–26°C
pH Range
✗ No overlap
Regan's Julie
8–9
Sixbar Distichodus
6–7.5
Hardness (dGH)
✓ Compatible
Regan's Julie
10–25
Sixbar Distichodus
10–20
Water Type
✓ Compatible
Regan's Julie
Freshwater Only
Sixbar Distichodus
Freshwater Only
Flow Preference
✓ Compatible
Regan's Julie
Moderate
Sixbar Distichodus
Moderate
Min Tank Volume
Combined: 1000 L
Regan's Julie
110 L
Sixbar Distichodus
1000 L
Swimming Level
Shared: 2 zones
Regan's Julie
BottomMiddle
Sixbar Distichodus
MiddleBottom
🏷️Behavior Tags
Regan's Julie
Territorial (Defends specific area)Aggressive to same species/look-alikesFry PredatorDigger (Disturbs Substrate)
Sixbar Distichodus
Plant DestroyerAggressive to same species/look-alikesJumper (Lid Required)Hyperactive / Fast SwimmerFin Nipper
Stocking calculator

Can your tank handle Regan's Julie and Sixbar Distichodus?

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.

Regan's Julie
Sixbar Distichodus
Test both in my tank

Behaviour & Temperament

Both Regan's Julie and Sixbar Distichodus are semi-aggressive species with an aggression score of 7/10. Their matching temperaments mean neither fish is likely to dominate the other in a shared aquarium.

Both Regan's Julie and Sixbar Distichodus are highly aggressive, increasing the risk of violent confrontations.

Regan's Julie and Sixbar Distichodus both frequent the Bottom (Substrate) 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.

Worth noting: Sixbar Distichodus 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 26°C. Aim for the midpoint of this range (around 24.5°C) for optimal comfort.

The pH requirements of Regan's Julie (8–9) and Sixbar Distichodus (6–7.5) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–20 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Regan's Julie and Sixbar Distichodus together, plan for an aquarium of at least 1000 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: Sand (Sifters), Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding). 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.

Why This Pairing Usually Fails in Practice

Regan's Julie and Sixbar Distichodus 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 Regan's Julie and Sixbar Distichodus live together?

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

What size tank do Regan's Julie and Sixbar Distichodus need?

A minimum of 1000 litres (tank length at least 200 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 Regan's Julie and Sixbar Distichodus together?

Keep the aquarium between 23°C and 26°C. A target of around 24.5°C sits comfortably within both species' preferred ranges.

Are Regan's Julie or Sixbar Distichodus aggressive?

Regan's Julie is semi-aggressive (7/10) and Sixbar Distichodus is semi-aggressive (7/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Regan's Julie and Sixbar Distichodus need?

Their pH requirements do not overlap. Regan's Julie prefers 8–9, while Sixbar Distichodus needs 6–7.5. This makes them incompatible in the same water chemistry.

Will Sixbar Distichodus nip Regan's Julie's fins?

Sixbar Distichodus is a known fin nipper. If Regan's Julie has long or flowing fins, there is a real risk of fin damage. Keeping Sixbar Distichodus in a larger group can help redirect nipping behaviour toward conspecifics.

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

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Regan'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 11, 2026
Last updated
May 11, 2026
Issues or corrections?
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