Keyhole Cichlid and Koi Compatibility Overview
Keyhole Cichlid and Koi are generally not recommended to be housed together. Koi is a cool-water fish and Keyhole Cichlid is tropical, so the usable temperature range decides this pairing. The adult size gap creates a meaningful predation risk. Review the behavior and water details before deciding whether to attempt the pairing.
| Factor | Keyhole Cichlid | Koi | Verdict |
|---|---|---|---|
| Temperature | 70โ82ยฐF | 50โ75ยฐF | โ 70โ75ยฐF |
| pH Range | 4.0โ7.5 | 7.0โ8.5 | โ ๏ธ 7.0โ7.5 (narrow) |
| Temperament | peaceful | peaceful | โ Compatible |
| Adult Size | 4.3 in | 24 in | โ 6ร difference |
| Min. Group | 2+ | 2+ | See below |
| Min. Tank Size | 100 gallons (for both species) | โ | |
Compatibility Positives
Incompatibility Reasons
Species Profiles
Keyhole Cichlid โ Cleithracara maronii
The Keyhole Cichlid is a popular choice for beginners due to its relatively easy care and peaceful temperament. These fish are known for their distinct keyhole marking and vibrant coloration. They do well in a community tank with other peaceful species, but should be provided with plenty of hiding spots to feel secure.
โ Full Keyhole Cichlid care guide
Koi โ Cyprinus rubrofuscus
Large pond fish that require hundreds of gallons and cool water. Will eat any fish small enough to fit in their mouth.
Frequently Asked Questions
Can Keyhole Cichlid live with Koi?
Generally not recommended. Keyhole Cichlid and Koi are generally not recommended to be housed together. Koi is a cool-water fish and Keyhole Cichlid is tropical, so the usable temperature range decides this pairing. The adult size gap creates a meaningful predation risk. Review the behavior and water details before deciding whether to attempt the pairing.
What tank size do I need for Keyhole Cichlid and Koi together?
A minimum of 100 gallons is recommended for keeping Keyhole Cichlid and Koi together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Keyhole Cichlid and Koi?
70โ75ยฐF โ inside Keyhole Cichlid's 70โ82ยฐF and Koi's 50โ75ยฐF.
Is a Keyhole Cichlid aggressive toward a Koi?
The adult size gap creates a meaningful predation risk.
Related Compatibility Guides
Tank Size for Keyhole Cichlid and Koi
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 100 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 150 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 180 gal | Best when keeping larger schools or reducing territorial pressure. |