Can Threadfin Rainbowfish and Yellow Peacock Cichlid Live Together?
Threadfin Rainbowfish and Yellow Peacock Cichlid 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
Can your tank handle Threadfin Rainbowfish and Yellow Peacock Cichlid?
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.
Behaviour & Temperament
Threadfin Rainbowfish is a peaceful species (1/10), while Yellow Peacock Cichlid is moderately assertive (6/10). This notable difference means Yellow Peacock Cichlid may occasionally assert dominance over Threadfin Rainbowfish.
Threadfin Rainbowfish and Yellow Peacock Cichlid 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: Threadfin Rainbowfish 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 28°C. Aim for the midpoint of this range (around 26.0°C) for optimal comfort.
The pH requirements of Threadfin Rainbowfish (5.5–7.5) and Yellow Peacock Cichlid (7.8–8.6) do not overlap, making it impossible to satisfy both species simultaneously.
For general hardness, the shared comfort zone is 10–12 dGH. Regular testing will ensure conditions stay within this range.
Tank Setup
To house Threadfin Rainbowfish and Yellow Peacock Cichlid 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 - Densely covered, Plants - Floating, Sand (Sifters). 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
Threadfin Rainbowfish and Yellow Peacock Cichlid 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 Threadfin Rainbowfish and Yellow Peacock Cichlid.
55 Gallon Standard
60 Gallon Breeder
75 Gallon Standard
90 Gallon Standard
125 Gallon Standard
150 Gallon High
Frequently Asked Questions
Can Threadfin Rainbowfish and Yellow Peacock Cichlid live together?
No. This combination is not recommended. Key incompatibilities — such as critical behavioural conflicts — make cohabitation unsafe.
What size tank do Threadfin Rainbowfish and Yellow Peacock Cichlid 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 Threadfin Rainbowfish and Yellow Peacock Cichlid together?
Keep the aquarium between 24°C and 28°C. A target of around 26.0°C sits comfortably within both species' preferred ranges.
Are Threadfin Rainbowfish or Yellow Peacock Cichlid aggressive?
Threadfin Rainbowfish is peaceful (1/10) and Yellow Peacock Cichlid 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 Threadfin Rainbowfish and Yellow Peacock Cichlid need?
Their pH requirements do not overlap. Threadfin Rainbowfish prefers 5.5–7.5, while Yellow Peacock Cichlid needs 7.8–8.6. This makes them incompatible in the same water chemistry.
How do I manage Yellow Peacock Cichlid's territorial behaviour?
Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Yellow Peacock Cichlid 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.
Shared setup supplies
We may earn from qualifying purchases
Guidarium Editorial Desk
Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.
- Last reviewed
- May 11, 2026
- Last updated
- May 11, 2026
- Issues or corrections?
- Contact the editorial team
Related Comparisons
Threadfin Rainbowfish & Honey Blue Eye
·
Threadfin Rainbowfish & Kabia rainbowfish
·
Threadfin Rainbowfish & Kiunga Blue Eye
·
Threadfin Rainbowfish & Lorentz's Rainbowfish
·
Threadfin Rainbowfish & Mamberamo Rainbowfish
·
Threadfin Rainbowfish & Ornate Rainbowfish
·
Yellow Peacock Cichlid & Afra Cichlid
·
Yellow Peacock Cichlid & African Jewel Cichlid
·
Yellow Peacock Cichlid & Altolamprologus Calvus
·
Yellow Peacock Cichlid & Altolamprologus Compressiceps
·
Yellow Peacock Cichlid & Aurora Yellow Mbuna
·
Yellow Peacock Cichlid & Black Diamond Cichlid
·