Can Domino Synodontis and Electric Blue Hap Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Not Recommended

Domino Synodontis and Electric Blue Hap 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

Domino Synodontis

Synodontis notatus

Electric Blue Hap

Sciaenochromis fryeri

🐠Family Group
Domino Synodontis
Catfish
Electric Blue Hap
Cichlids - African
Temperament
Domino Synodontis
Semi-Aggressive (6/10)
Electric Blue Hap
Aggressive (7/10)
Temperature
✓ Compatible
Domino Synodontis
22–26°C
Electric Blue Hap
24–28°C
pH Range
✗ No overlap
Domino Synodontis
6–7.5
Electric Blue Hap
7.8–8.6
Hardness (dGH)
✓ Compatible
Domino Synodontis
4–18
Electric Blue Hap
10–25
Water Type
✓ Compatible
Domino Synodontis
Freshwater Only
Electric Blue Hap
Freshwater Only
Flow Preference
✓ Compatible
Domino Synodontis
Moderate
Electric Blue Hap
Moderate
Min Tank Volume
Combined: 250 L
Domino Synodontis
250 L
Electric Blue Hap
200 L
Swimming Level
Shared: 2 zones
Domino Synodontis
MiddleBottom
Electric Blue Hap
MiddleBottom
🏷️Behavior Tags
Domino Synodontis
Piscivore (Eats small/nano fish)Aggressive to same species/look-alikesTerritorial (Defends specific area)Hyperactive / Fast Swimmer
Electric Blue Hap
Piscivore (Eats small/nano fish)Fry PredatorAggressive to same species/look-alikesTerritorial (Defends specific area)Hyperactive / Fast Swimmer
Stocking calculator

Can your tank handle Domino Synodontis and Electric Blue Hap?

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.

Domino Synodontis
Electric Blue Hap
Test both in my tank

Behaviour & Temperament

Domino Synodontis is a moderately assertive species (6/10), while Electric Blue Hap is semi-aggressive (7/10). This modest difference means Electric Blue Hap may occasionally assert dominance over Domino Synodontis.

Domino Synodontis and Electric Blue Hap both frequent the Middle (Open Water) and Bottom (Substrate) 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.

Water Parameters

The safe temperature window for both species falls between 24°C and 26°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

The pH requirements of Domino Synodontis (6–7.5) and Electric Blue Hap (7.8–8.6) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–18 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Domino Synodontis and Electric Blue Hap together, plan for an aquarium of at least 250 litres with a minimum length of 120 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), Driftwood (Digestion/Hiding), Sand (Sifters). 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

Domino Synodontis and Electric Blue Hap 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 Domino Synodontis and Electric Blue Hap.

Show 1 more tank size

Frequently Asked Questions

Can Domino Synodontis and Electric Blue Hap live together?

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

What size tank do Domino Synodontis and Electric Blue Hap need?

A minimum of 250 litres (tank length at least 120 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 Domino Synodontis and Electric Blue Hap together?

Keep the aquarium between 24°C and 26°C. A target of around 25.0°C sits comfortably within both species' preferred ranges.

Are Domino Synodontis or Electric Blue Hap aggressive?

Domino Synodontis is moderately assertive (6/10) and Electric Blue Hap is semi-aggressive (7/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Domino Synodontis and Electric Blue Hap need?

Their pH requirements do not overlap. Domino Synodontis prefers 6–7.5, while Electric Blue Hap needs 7.8–8.6. This makes them incompatible in the same water chemistry.

How do I manage Domino Synodontis's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Domino Synodontis 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 4, 2026
Last updated
May 4, 2026
Issues or corrections?
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