Can Blue Dolphin (Hap) and Rachov's Killifish (Annual) Live Together?

🟢Ideal Tank Mates

Yes, Blue Dolphin (Hap) and Rachov's Killifish (Annual) are ideal tank mates. Both species share compatible water parameters and peaceful temperaments, making them well-suited for a community aquarium. A minimum tank size of 570 litres is recommended.


At a Glance

Blue Dolphin (Hap)

Cyrtocara moorii

Rachov's Killifish (Annual)

Nothobranchius rachovii

🐠Family Group
Blue Dolphin (Hap)
Cichlids - African
Rachov's Killifish (Annual)
Killifish
Temperament
Blue Dolphin (Hap)
Semi-Aggressive (5/10)
Rachov's Killifish (Annual)
Mostly Peaceful (3/10)
Temperature
✓ Compatible
Blue Dolphin (Hap)
24–28°C
Rachov's Killifish (Annual)
20–26°C
pH Range
✓ Compatible
Blue Dolphin (Hap)
7.5–8.6
Rachov's Killifish (Annual)
6–7.5
Hardness (dGH)
✓ Compatible
Blue Dolphin (Hap)
10–25
Rachov's Killifish (Annual)
4–12
Water Type
✓ Compatible
Blue Dolphin (Hap)
Freshwater Only
Rachov's Killifish (Annual)
Freshwater Only
Flow Preference
✓ Compatible
Blue Dolphin (Hap)
Moderate
Rachov's Killifish (Annual)
Low
Min Tank Volume
Combined: 570 L
Blue Dolphin (Hap)
475 L
Rachov's Killifish (Annual)
19 L
Swimming Level
Shared: 2 zones
Blue Dolphin (Hap)
MiddleBottom
Rachov's Killifish (Annual)
MiddleBottom
🏷️Behavior Tags
Blue Dolphin (Hap)
Digger (Disturbs Substrate)Hyperactive / Fast SwimmerAggressive to same species/look-alikes
Rachov's Killifish (Annual)
Nano / Bite-sized (Predation Risk)Hyperactive / Fast SwimmerJumper (Lid Required)

Behaviour & Temperament

Blue Dolphin (Hap) is a moderately assertive species (5/10), while Rachov's Killifish (Annual) is generally mild-mannered (3/10). This modest difference means Blue Dolphin (Hap) may occasionally assert dominance over Rachov's Killifish (Annual).

Blue Dolphin (Hap) and Rachov's Killifish (Annual) 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.

Worth noting: Rachov's Killifish (Annual) 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 26°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

Both fish can tolerate a pH between 7.5 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 10–12 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Blue Dolphin (Hap) and Rachov's Killifish (Annual) together, plan for an aquarium of at least 570 litres with a minimum length of 150 cm. This accounts for the larger species' space requirements with an additional 20 % buffer to reduce territorial tension.

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), Soil / Nutrient Rich, Leaf Litter/Blackwater, Plants - Densely covered. Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Blue Dolphin (Hap) requires Sand (Sifters), while Rachov's Killifish (Annual) requires Soil / Nutrient Rich. These substrate types may be difficult to provide simultaneously. Blue Dolphin (Hap) requires Smooth Gravel (Sensitive Barbels), while Rachov's Killifish (Annual) requires Soil / Nutrient Rich. These substrate types may be difficult to provide simultaneously. Compromise where possible or prioritise the more critical need.

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

Frequently Asked Questions

Can Blue Dolphin (Hap) and Rachov's Killifish (Annual) live together?

Yes. Blue Dolphin (Hap) and Rachov's Killifish (Annual) are considered ideal tank mates. Their water parameters, temperaments, and behaviour profiles are well matched for a community aquarium.

What size tank do Blue Dolphin (Hap) and Rachov's Killifish (Annual) need?

A minimum of 570 litres (tank length at least 150 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 Blue Dolphin (Hap) and Rachov's Killifish (Annual) 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 Blue Dolphin (Hap) or Rachov's Killifish (Annual) aggressive?

Blue Dolphin (Hap) is moderately assertive (5/10) and Rachov's Killifish (Annual) is generally mild-mannered (3/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Blue Dolphin (Hap) and Rachov's Killifish (Annual) need?

Both species overlap in the 7.5–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.


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