Can African Lungfish and Marlier's Julie Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 6, 2026
Not Recommended

African Lungfish 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

African Lungfish

Protopterus annectens

Marlier's Julie

Julidochromis marlieri

🐠Family Group
African Lungfish
Oddballs
Marlier's Julie
Cichlids - African
Temperament
African Lungfish
Highly Aggressive (10/10)
Marlier's Julie
Semi-Aggressive (6/10)
Temperature
✓ Compatible
African Lungfish
24–30°C
Marlier's Julie
23–27°C
pH Range
✗ No overlap
African Lungfish
6–8
Marlier's Julie
8.2–9.3
Hardness (dGH)
✓ Compatible
African Lungfish
5–20
Marlier's Julie
10–25
Water Type
✓ Compatible
African Lungfish
Freshwater Only
Marlier's Julie
Freshwater Only
Flow Preference
✓ Compatible
African Lungfish
Low
Marlier's Julie
Moderate
Min Tank Volume
Combined: 680 L
African Lungfish
680 L
Marlier's Julie
114 L
Swimming Level
Shared: 2 zones
African Lungfish
BottomMiddleTop
Marlier's Julie
BottomMiddle
🏷️Behavior Tags
African Lungfish
Piscivore (Eats small/nano fish)Generally AggressiveAggressive to same species/look-alikesJumper (Lid Required)Digger (Disturbs Substrate)Plant DestroyerTerritorial (Defends specific area)
Marlier's Julie
Territorial (Defends specific area)Aggressive to same species/look-alikesDigger (Disturbs Substrate)Fry Predator
Stocking calculator

Can your tank handle African Lungfish 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.

African Lungfish
Marlier's Julie
Test both in my tank

Behaviour & Temperament

African Lungfish is a highly aggressive species (10/10), while Marlier's Julie is moderately assertive (6/10). This notable difference means African Lungfish may occasionally assert dominance over Marlier's Julie.

African Lungfish and Marlier's Julie 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.

Additional behavioural considerations to keep in mind: Two territorial species may clash over territory, especially in smaller tanks.

Worth noting: African Lungfish is a known jumper, so a tight-fitting lid is essential.

Water Parameters

The safe temperature window for both species falls between 24°C and 27°C. Aim for the midpoint of this range (around 25.5°C) for optimal comfort.

The pH requirements of African Lungfish (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 10–20 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house African Lungfish and Marlier's Julie together, plan for an aquarium of at least 680 litres with a minimum length of 180 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 low (still water) water movement, so a standard filtration setup rated for the tank volume should suffice.

Why This Pairing Usually Fails in Practice

African Lungfish 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.

Suitable Tank Sizes

Standard aquarium sizes large enough for both African Lungfish and Marlier's Julie.

Frequently Asked Questions

Can African Lungfish 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 African Lungfish and Marlier's Julie need?

A minimum of 680 litres (tank length at least 180 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 African Lungfish and Marlier's Julie together?

Keep the aquarium between 24°C and 27°C. A target of around 25.5°C sits comfortably within both species' preferred ranges.

Are African Lungfish or Marlier's Julie aggressive?

African Lungfish is highly aggressive (10/10) and Marlier's Julie is moderately assertive (6/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do African Lungfish and Marlier's Julie need?

Their pH requirements do not overlap. African Lungfish 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 African Lungfish's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives African Lungfish 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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