๐Ÿ  Fish Compatibility Guide

Can Black Ghost Knifefish and Pea Puffer Live Together?

Updated September 23, 2026 ยท FishCare AI Editorial Team

โŒ Not Compatible โ€” Compatibility Score: 32/100
32/100 โ€” Not Compatible

Black Ghost Knifefish and Pea Puffer Compatibility Overview

Black Ghost Knifefish and Pea Puffer are generally not recommended to be housed together. The adult size gap creates a meaningful predation risk. Both are semi, so give them a larger, well-planted tank and watch how they settle in. Review the behavior and water details before deciding whether to attempt the pairing.

Compatibility factors for Black Ghost Knifefish and Pea Puffer
FactorBlack Ghost KnifefishPea PufferVerdict
Temperature73โ€“82ยฐF74โ€“82ยฐFโœ… 74โ€“82ยฐF
pH Range6.0โ€“8.07.0โ€“8.0โœ… 7.0โ€“8.0
Temperamentsemisemiโš ๏ธ Monitor
Adult Size18.0 in1 inโŒ 18ร— difference
Min. Group1+1+See below
Min. Tank Size100 gallons (for both species)โ€”

Compatibility Positives

A stable shared temperature range is available.
Their pH requirements overlap.

Incompatibility Reasons

The adult size gap creates a meaningful predation risk.
Both are semi, so give them a larger, well-planted tank and watch how they settle in.

Species Profiles

Black Ghost Knifefish โ€” Apteronotus albifrons

Black Ghost Knifefish and Pea Puffer compatibility โ€” Black Ghost Knifefish

The Black Ghost Knifefish is a unique and elegant addition to the aquarium. With a lifespan of 5-8 years, it requires a minimum tank size of 200 liters. It is a solitary fish with a low aggression level and moderate activity. Its slender body and silver-blue coloration make it a captivating sight.

โ†’ Full Black Ghost Knifefish care guide

Pea Puffer โ€” Carinotetraodon travancoricus

Black Ghost Knifefish and Pea Puffer compatibility โ€” Pea Puffer

World's smallest pufferfish โ€” intensely territorial and nippy despite tiny size. Will attack fins and eat shrimp and snails.

โ†’ Full Pea Puffer care guide

Frequently Asked Questions

Can Black Ghost Knifefish live with Pea Puffer?

Generally not recommended. Black Ghost Knifefish and Pea Puffer are generally not recommended to be housed together. The adult size gap creates a meaningful predation risk. Both are semi, so give them a larger, well-planted tank and watch how they settle in. Review the behavior and water details before deciding whether to attempt the pairing.

What tank size do I need for Black Ghost Knifefish and Pea Puffer together?

A minimum of 100 gallons is recommended for keeping Black Ghost Knifefish and Pea Puffer together. A larger tank improves water stability and reduces territorial conflict.

What temperature suits both Black Ghost Knifefish and Pea Puffer?

74โ€“82ยฐF โ€” inside Black Ghost Knifefish's 73โ€“82ยฐF and Pea Puffer's 74โ€“82ยฐF.

Is a Black Ghost Knifefish aggressive toward a Pea Puffer?

The adult size gap creates a meaningful predation risk.

Related Compatibility Guides

Tank Size for Black Ghost Knifefish and Pea Puffer

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

ScenarioTankWhen it applies
Minimum viable100 galOnly for the recommended minimum groups, mature filtration, and close monitoring.
Recommended community150 galAdds territory, swimming room, and a safer buffer for behavior.
Low-conflict setup180 galBest when keeping larger schools or reducing territorial pressure.