๐Ÿ  Fish Compatibility Guide

Can Black Phantom Tetra and Threadfin Rainbowfish Live Together?

Updated September 23, 2026 ยท FishCare AI Editorial Team

โœ… Compatible โ€” Compatibility Score: 90/100
90/100 โ€” Compatible

Black Phantom Tetra and Threadfin Rainbowfish Compatibility Overview

Black Phantom Tetra and Threadfin Rainbowfish can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges. Both species are peaceful, and neither poses a major aggression risk to the other. A minimum 20-gallon tank is recommended to provide adequate territory and water volume for both species.

Compatibility factors for Black Phantom Tetra and Threadfin Rainbowfish
FactorBlack Phantom TetraThreadfin RainbowfishVerdict
Temperature68โ€“82ยฐF72โ€“86ยฐFโœ… 72โ€“82ยฐF
pH Range5.0โ€“7.05.0โ€“8.0โœ… 5.0โ€“7.0
Temperamentpeacefulpeacefulโœ… Compatible
Adult Size1.4 in1.6 inโœ… Similar
Min. Group8+6+See below
Min. Tank Size20 gallons (for both species)โ€”

Compatibility Positives

A stable shared temperature range is available.
Their pH requirements overlap.
Temperament risk is relatively low when normal group sizes are maintained.

Caution Points

No major compatibility issues identified for this pair.

Species Profiles

Black Phantom Tetra โ€” Hyphessobrycon megalopterus

Black Phantom Tetra and Threadfin Rainbowfish compatibility โ€” Black Phantom Tetra

The Black Phantom Tetra is a popular freshwater fish known for its striking black and silver coloration. It is generally peaceful and can be kept in a community tank with other non-aggressive species. They require a well-maintained tank with a moderate water flow and a good cover of plants.

โ†’ Full Black Phantom Tetra care guide

Threadfin Rainbowfish โ€” Iriatherina werneri

Black Phantom Tetra and Threadfin Rainbowfish compatibility โ€” Threadfin Rainbowfish

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.

โ†’ Full Threadfin Rainbowfish care guide

Frequently Asked Questions

Can Black Phantom Tetra live with Threadfin Rainbowfish?

Yes, in a well-planned setup. Black Phantom Tetra and Threadfin Rainbowfish can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges. Both species are peaceful, and neither poses a major aggression risk to the other. A minimum 20-gallon tank is recommended to provide adequate territory and water volume for both species.

What tank size do I need for Black Phantom Tetra and Threadfin Rainbowfish together?

A minimum of 20 gallons is recommended for keeping Black Phantom Tetra and Threadfin Rainbowfish together. A larger tank improves water stability and reduces territorial conflict.

What temperature suits both Black Phantom Tetra and Threadfin Rainbowfish?

72โ€“82ยฐF โ€” inside Black Phantom Tetra's 68โ€“82ยฐF and Threadfin Rainbowfish's 72โ€“86ยฐF.

Is a Black Phantom Tetra aggressive toward a Threadfin Rainbowfish?

Black Phantom Tetra is peaceful and Threadfin Rainbowfish is peaceful. No major aggression issues are expected between these species.

Related Compatibility Guides

Tank Size for Black Phantom Tetra and Threadfin Rainbowfish

Use the scenario that matches the actual group sizes and temperament you plan to keep.

ScenarioTankWhen it applies
Minimum viable20 galOnly for the recommended minimum groups, mature filtration, and close monitoring.
Recommended community29 galAdds territory, swimming room, and a safer buffer for behavior.
Low-conflict setup55 galBest when keeping larger schools or reducing territorial pressure.