Cardinal Tetra and Lionfish Compatibility Overview
Cardinal Tetra and Lionfish are generally not recommended to be housed together. One of these is a marine species and the other is not; they cannot share one aquarium. The adult size gap creates a meaningful predation risk. Review the behavior and water details before deciding whether to attempt the pairing.
| Factor | Cardinal Tetra | Lionfish | Verdict |
|---|---|---|---|
| Temperature | 73โ82ยฐF | 72โ82ยฐF | โ 73โ82ยฐF |
| pH Range | 4.5โ7.0 | 8.1โ8.4 | โ No overlap |
| Temperament | peaceful | aggressive | โ Risk |
| Adult Size | 1.5 in | 15.0 in | โ 10ร difference |
| Min. Group | 6+ | 1+ | See below |
| Min. Tank Size | 100 gallons (for both species) | โ | |
Compatibility Positives
Incompatibility Reasons
Species Profiles
Cardinal Tetra โ Paracheirodon axelrodi
Brilliant red-and-blue schooling fish from the Rio Negro. Prefers soft, acidic, warm water โ a natural companion for discus.
โ Full Cardinal Tetra care guide
Lionfish โ Pterois volitans
Lionfish are popular saltwater aquarium fish known for their striking colors and intimidating spines. These fish require a large tank and careful attention to water parameters. Aggressive by nature, they can be harmful to smaller fish and invertebrates.
Frequently Asked Questions
Can Cardinal Tetra live with Lionfish?
Generally not recommended. Cardinal Tetra and Lionfish are generally not recommended to be housed together. One of these is a marine species and the other is not; they cannot share one aquarium. 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 Cardinal Tetra and Lionfish together?
A minimum of 100 gallons is recommended for keeping Cardinal Tetra and Lionfish together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Cardinal Tetra and Lionfish?
73โ82ยฐF โ inside Cardinal Tetra's 73โ82ยฐF and Lionfish's 72โ82ยฐF.
Is a Cardinal Tetra aggressive toward a Lionfish?
The adult size gap creates a meaningful predation risk.
Related Compatibility Guides
Tank Size for Cardinal Tetra and Lionfish
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 120 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 180 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. |