Congo Tetra and Koi Compatibility Overview
Congo Tetra and Koi are generally not recommended to be housed together. Koi is a cool-water fish and Congo Tetra 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 | Congo Tetra | Koi | Verdict |
|---|---|---|---|
| Temperature | 73โ82ยฐF | 50โ75ยฐF | โ ๏ธ 73โ75ยฐF (narrow) |
| pH Range | 6.0โ7.5 | 7.0โ8.5 | โ ๏ธ 7.0โ7.5 (narrow) |
| Temperament | peaceful | peaceful | โ Compatible |
| Adult Size | 3.1 in | 24 in | โ 8ร difference |
| Min. Group | 6+ | 2+ | See below |
| Min. Tank Size | 100 gallons (for both species) | โ | |
Compatibility Positives
Incompatibility Reasons
Species Profiles
Congo Tetra โ Phenacogrammus interruptus
The Congo Tetra is a vibrant and active fish that thrives in a well-maintained freshwater aquarium. With its striking coloration and peaceful nature, it's a great addition to any community tank. This species is best kept in groups and requires a spacious tank with plenty of swimming space.
โ Full Congo Tetra 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 Congo Tetra live with Koi?
Generally not recommended. Congo Tetra and Koi are generally not recommended to be housed together. Koi is a cool-water fish and Congo Tetra 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 Congo Tetra and Koi together?
A minimum of 100 gallons is recommended for keeping Congo Tetra and Koi together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Congo Tetra and Koi?
73โ75ยฐF (narrow) โ inside Congo Tetra's 73โ82ยฐF and Koi's 50โ75ยฐF.
Is a Congo Tetra aggressive toward a Koi?
The adult size gap creates a meaningful predation risk.
Related Compatibility Guides
Tank Size for Congo Tetra 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 | 220 gal | Best when keeping larger schools or reducing territorial pressure. |