Can Clown Killifish and Electric Blue Hap Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Not Recommended

Clown Killifish and Electric Blue Hap are not recommended as tank mates due to conflicting pH requirements and incompatible hardness ranges and piscivorous fish will prey on nano-sized tank mates.. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Clown Killifish

Epiplatys annulatus

Electric Blue Hap

Sciaenochromis fryeri

🐠Family Group
Clown Killifish
Killifish
Electric Blue Hap
Cichlids - African
Temperament
Clown Killifish
Peaceful (2/10)
Electric Blue Hap
Aggressive (7/10)
Temperature
✓ Compatible
Clown Killifish
23–27°C
Electric Blue Hap
24–28°C
pH Range
✗ No overlap
Clown Killifish
5–7
Electric Blue Hap
7.8–8.6
Hardness (dGH)
✗ No overlap
Clown Killifish
1–8
Electric Blue Hap
10–25
Water Type
✓ Compatible
Clown Killifish
Freshwater Only
Electric Blue Hap
Freshwater Only
Flow Preference
✓ Compatible
Clown Killifish
Low
Electric Blue Hap
Moderate
Min Tank Volume
Combined: 200 L
Clown Killifish
19 L
Electric Blue Hap
200 L
Swimming Level
✓ Different zones
Clown Killifish
Top
Electric Blue Hap
MiddleBottom
🏷️Behavior Tags
Clown Killifish
Nano / Bite-sized (Predation Risk)Jumper (Lid Required)Shy / Slow Moving (Easily Stressed)Fry Predator
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 Clown Killifish 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.

Clown Killifish
Electric Blue Hap
Test both in my tank

Behaviour & Temperament

Clown Killifish is a peaceful species (2/10), while Electric Blue Hap is semi-aggressive (7/10). This notable difference means Electric Blue Hap may occasionally assert dominance over Clown Killifish.

In terms of spatial distribution, Clown Killifish prefers the Top (Surface) zone, whereas Electric Blue Hap occupies the Middle (Open Water) and Bottom (Substrate) zones. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

There is a critical concern: the Nano / Bite-sized (Predation Risk) behaviour of one fish directly conflicts with the Piscivore (Eats small/nano fish) trait of the other — piscivorous fish will prey on nano-sized tank mates..

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Clown Killifish 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 Clown Killifish (5–7) and Electric Blue Hap (7.8–8.6) do not overlap, making it impossible to satisfy both species simultaneously.

Hardness requirements are incompatible: Clown Killifish needs 1–8 dGH while Electric Blue Hap requires 10–25 dGH.

Tank Setup

To house Clown Killifish and Electric Blue Hap together, plan for an aquarium of at least 200 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: Plants - Floating, Plants - Densely covered, Leaf Litter/Blackwater, Sand (Sifters), Smooth Gravel (Sensitive Barbels). 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

Clown Killifish 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 Clown Killifish and Electric Blue Hap.

Show 5 more tank sizes

Frequently Asked Questions

Can Clown Killifish 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 Clown Killifish and Electric Blue Hap need?

A minimum of 200 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 Clown Killifish and Electric Blue Hap 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 Clown Killifish or Electric Blue Hap aggressive?

Clown Killifish is peaceful (2/10) and Electric Blue Hap is semi-aggressive (7/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Clown Killifish and Electric Blue Hap need?

Their pH requirements do not overlap. Clown Killifish prefers 5–7, while Electric Blue Hap needs 7.8–8.6. This makes them incompatible in the same water chemistry.

How do I manage Electric Blue Hap's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Electric Blue Hap 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?
Contact the editorial team

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