๐Ÿ  Fish Compatibility Guide

Can Congo Tetra and Lionfish Live Together?

Updated September 23, 2026 ยท FishCare AI Editorial Team

โŒ Not Compatible โ€” Compatibility Score: 0/100
0/100 โ€” Not Compatible

Congo Tetra and Lionfish Compatibility Overview

Congo 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.

Compatibility factors for Congo Tetra and Lionfish
FactorCongo TetraLionfishVerdict
Temperature73โ€“82ยฐF72โ€“82ยฐFโœ… 73โ€“82ยฐF
pH Range6.0โ€“7.58.1โ€“8.4โŒ No overlap
TemperamentpeacefulaggressiveโŒ Risk
Adult Size3.1 in15.0 inโŒ 5ร— difference
Min. Group6+1+See below
Min. Tank Size100 gallons (for both species)โ€”

Compatibility Positives

A stable shared temperature range is available.

Incompatibility Reasons

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.
Their pH ranges do not meet: Congo Tetra wants 6.0โ€“7.5 and Lionfish wants 8.1โ€“8.4.
Congo Tetra is peaceful and Lionfish is aggressive. Expect chasing and fin damage unless the tank is oversized, heavily planted, and watched closely.

Species Profiles

Congo Tetra โ€” Phenacogrammus interruptus

Congo Tetra and Lionfish compatibility โ€” Congo Tetra

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

Lionfish โ€” Pterois volitans

Congo Tetra and Lionfish compatibility โ€” Lionfish

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.

โ†’ Full Lionfish care guide

Frequently Asked Questions

Can Congo Tetra live with Lionfish?

Generally not recommended. Congo 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 Congo Tetra and Lionfish together?

A minimum of 100 gallons is recommended for keeping Congo Tetra and Lionfish together. A larger tank improves water stability and reduces territorial conflict.

What temperature suits both Congo Tetra and Lionfish?

73โ€“82ยฐF โ€” inside Congo Tetra's 73โ€“82ยฐF and Lionfish's 72โ€“82ยฐF.

Is a Congo Tetra aggressive toward a Lionfish?

The adult size gap creates a meaningful predation risk.

Related Compatibility Guides

Tank Size for Congo Tetra and Lionfish

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

ScenarioTankWhen it applies
Minimum viable120 galOnly for the recommended minimum groups, mature filtration, and close monitoring.
Recommended community180 galAdds territory, swimming room, and a safer buffer for behavior.
Low-conflict setup220 galBest when keeping larger schools or reducing territorial pressure.