Can Rachov's Killifish (Annual) and Turquoise Rainbowfish Live Together?

Reviewed by Guidarium Editorial DeskUpdated April 28, 2026
Ideal Tank Mates

Yes, Rachov's Killifish (Annual) and Turquoise Rainbowfish 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 160 litres is recommended.


At a Glance

Rachov's Killifish (Annual)

Nothobranchius rachovii

Turquoise Rainbowfish

Melanotaenia lacustris

🐠Family Group
Rachov's Killifish (Annual)
Killifish
Turquoise Rainbowfish
Rainbowfish
Temperament
Rachov's Killifish (Annual)
Mostly Peaceful (3/10)
Turquoise Rainbowfish
Peaceful (2/10)
Temperature
✓ Compatible
Rachov's Killifish (Annual)
20–26°C
Turquoise Rainbowfish
20–25°C
pH Range
✓ Compatible
Rachov's Killifish (Annual)
6–7.5
Turquoise Rainbowfish
7–9
Hardness (dGH)
✓ Compatible
Rachov's Killifish (Annual)
4–12
Turquoise Rainbowfish
10–25
Water Type
✓ Compatible
Rachov's Killifish (Annual)
Freshwater Only
Turquoise Rainbowfish
Freshwater Only
Flow Preference
✓ Compatible
Rachov's Killifish (Annual)
Low
Turquoise Rainbowfish
Moderate
Min Tank Volume
Combined: 160 L
Rachov's Killifish (Annual)
19 L
Turquoise Rainbowfish
160 L
Swimming Level
Shared: 1 zone
Rachov's Killifish (Annual)
MiddleBottom
Turquoise Rainbowfish
TopMiddle
🏷️Behavior Tags
Rachov's Killifish (Annual)
Nano / Bite-sized (Predation Risk)Hyperactive / Fast SwimmerJumper (Lid Required)
Turquoise Rainbowfish
Hyperactive / Fast SwimmerJumper (Lid Required)Aggressive Eater (Starves shy fish)
Stocking calculator

Can your tank handle Rachov's Killifish (Annual) and Turquoise Rainbowfish?

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.

Rachov's Killifish (Annual)
Turquoise Rainbowfish
Test both in my tank

Behaviour & Temperament

Rachov's Killifish (Annual) is a generally mild-mannered species (3/10), while Turquoise Rainbowfish is peaceful (2/10). This modest difference means Rachov's Killifish (Annual) may occasionally assert dominance over Turquoise Rainbowfish.

Rachov's Killifish (Annual) and Turquoise Rainbowfish both frequent the 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: 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 20°C and 25°C. Aim for the midpoint of this range (around 22.5°C) for optimal comfort.

Both fish can tolerate a pH between 7 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 Rachov's Killifish (Annual) and Turquoise Rainbowfish together, plan for an aquarium of at least 160 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: Soil / Nutrient Rich, Leaf Litter/Blackwater, Plants - Densely covered, Plants - lighly covered. 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 Works in Practice

Rachov's Killifish (Annual) and Turquoise Rainbowfish work best when the tank gives each fish enough room to use its preferred level of the aquarium and enough cover to avoid constant visual contact. The score matters, but the real-world success usually comes from matching their pace, keeping water stable, and resisting the urge to crowd the tank just because the pair looks safe on paper.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Rachov's Killifish (Annual) and Turquoise Rainbowfish.

Show 5 more tank sizes

Frequently Asked Questions

Can Rachov's Killifish (Annual) and Turquoise Rainbowfish live together?

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

What size tank do Rachov's Killifish (Annual) and Turquoise Rainbowfish need?

A minimum of 160 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 Rachov's Killifish (Annual) and Turquoise Rainbowfish together?

Keep the aquarium between 20°C and 25°C. A target of around 22.5°C sits comfortably within both species' preferred ranges.

Are Rachov's Killifish (Annual) or Turquoise Rainbowfish aggressive?

Rachov's Killifish (Annual) is generally mild-mannered (3/10) and Turquoise Rainbowfish is peaceful (2/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Rachov's Killifish (Annual) and Turquoise Rainbowfish need?

Both species overlap in the 7–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
April 28, 2026
Last updated
April 28, 2026
Issues or corrections?
Contact the editorial team

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