Fire Eel and Threadfin Rainbowfish Compatibility Overview
Fire Eel and Threadfin Rainbowfish are generally not recommended to be housed together. The adult size gap creates a meaningful predation risk. Review the behavior and water details before deciding whether to attempt the pairing.
| Factor | Fire Eel | Threadfin Rainbowfish | Verdict |
|---|---|---|---|
| Temperature | 75โ82ยฐF | 72โ86ยฐF | โ 75โ82ยฐF |
| pH Range | 6.0โ7.0 | 5.0โ8.0 | โ 6.0โ7.0 |
| Temperament | semi | peaceful | โ ๏ธ Monitor |
| Adult Size | 39.4 in | 1.6 in | โ 25ร difference |
| Min. Group | 1+ | 6+ | See below |
| Min. Tank Size | 100 gallons (for both species) | โ | |
Compatibility Positives
Incompatibility Reasons
Species Profiles
Fire Eel โ Mastacembelus erythrotaenia
The Fire Eel is a stunning, red-bottomed species that requires a spacious tank. They are peaceful bottom feeders and do best in a well-planted, mature aquarium. With a moderate activity level, they can be a great addition to a community tank, but their size and diet may be incompatible with smaller fish.
Threadfin Rainbowfish โ Iriatherina werneri
The Threadfin Rainbowfish is a popular choice for freshwater aquariums due to its vibrant colors and peaceful nature. It requires a well-maintained tank with plenty of swimming space and a moderate water flow. These fish are not known to be aggressive and can be kept in community tanks with other peaceful species.
Frequently Asked Questions
Can Fire Eel live with Threadfin Rainbowfish?
Generally not recommended. Fire Eel and Threadfin Rainbowfish are generally not recommended to be housed together. 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 Fire Eel and Threadfin Rainbowfish together?
A minimum of 100 gallons is recommended for keeping Fire Eel and Threadfin Rainbowfish together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Fire Eel and Threadfin Rainbowfish?
75โ82ยฐF โ inside Fire Eel's 75โ82ยฐF and Threadfin Rainbowfish's 72โ86ยฐF.
Is a Fire Eel aggressive toward a Threadfin Rainbowfish?
The adult size gap creates a meaningful predation risk.
Related Compatibility Guides
Tank Size for Fire Eel and Threadfin Rainbowfish
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 114 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. |