Can Cupid Cichlid and Redtail Splitfin Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Not Recommended

Cupid Cichlid and Redtail Splitfin are not recommended as tank mates due to incompatible hardness ranges. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Cupid Cichlid

Biotodoma cupido

Redtail Splitfin

Xenotoca eiseni

🐠Family Group
Cupid Cichlid
Cichlids - South American
Redtail Splitfin
Livebearers
Temperament
Cupid Cichlid
Mostly Peaceful (3/10)
Redtail Splitfin
Semi-Aggressive (6/10)
Temperature
✓ Compatible
Cupid Cichlid
24–29°C
Redtail Splitfin
18–26°C
pH Range
✓ Compatible
Cupid Cichlid
5–7
Redtail Splitfin
7–8.5
Hardness (dGH)
✗ No overlap
Cupid Cichlid
1–8
Redtail Splitfin
10–25
Water Type
✓ Compatible
Cupid Cichlid
Freshwater Only
Redtail Splitfin
Freshwater Only
Flow Preference
✓ Compatible
Cupid Cichlid
Low
Redtail Splitfin
Moderate
Min Tank Volume
Combined: 250 L
Cupid Cichlid
250 L
Redtail Splitfin
110 L
Swimming Level
Shared: 1 zone
Cupid Cichlid
MiddleBottom
Redtail Splitfin
TopMiddle
🏷️Behavior Tags
Cupid Cichlid
Digger (Disturbs Substrate)Shy / Slow Moving (Easily Stressed)
Redtail Splitfin
Fin NipperFry PredatorHyperactive / Fast SwimmerPlant Destroyer
Stocking calculator

Can your tank handle Cupid Cichlid and Redtail Splitfin?

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.

Cupid Cichlid
Redtail Splitfin
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Behaviour & Temperament

Cupid Cichlid is a generally mild-mannered species (3/10), while Redtail Splitfin is moderately assertive (6/10). This modest difference means Redtail Splitfin may occasionally assert dominance over Cupid Cichlid.

Cupid Cichlid and Redtail Splitfin 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.

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

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 and 7. Maintaining a stable value within this band is more important than hitting an exact number.

Hardness requirements are incompatible: Cupid Cichlid needs 1–8 dGH while Redtail Splitfin requires 10–25 dGH.

Tank Setup

To house Cupid Cichlid and Redtail Splitfin 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: Sand (Sifters), Driftwood (Digestion/Hiding), Leaf Litter/Blackwater, Plants - Densely covered, Established Algae (Otocinclus). 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

Cupid Cichlid and Redtail Splitfin 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 Cupid Cichlid and Redtail Splitfin.

Show 1 more tank size

Frequently Asked Questions

Can Cupid Cichlid and Redtail Splitfin live together?

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

What size tank do Cupid Cichlid and Redtail Splitfin 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 Cupid Cichlid and Redtail Splitfin 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 Cupid Cichlid or Redtail Splitfin aggressive?

Cupid Cichlid is generally mild-mannered (3/10) and Redtail Splitfin is moderately assertive (6/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Cupid Cichlid and Redtail Splitfin need?

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

Will Redtail Splitfin nip Cupid Cichlid's fins?

Redtail Splitfin is a known fin nipper. If Cupid Cichlid has long or flowing fins, there is a real risk of fin damage. Keeping Redtail Splitfin in a larger group can help redirect nipping behaviour toward conspecifics.

Editorial Review

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?
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