Compatibility Overview
Green Terror Cichlid and Pajama Cardinalfish are generally not recommended to be housed together. The issues listed above — whether water parameter incompatibility, predation risk, or aggression — create conditions where one or both fish are likely to suffer harm or chronic stress.
| Factor | Green Terror Cichlid | Pajama Cardinalfish | Verdict |
|---|---|---|---|
| Temperature | 72–82°F | 72–82°F | ✅ 72–82°F |
| pH Range | 6.0–8.0 | 8.0–8.3 | ⚠️ 8.0–8.0 (narrow) |
| Temperament | aggressive | semi | ❌ Risk |
| Adult Size | 3.9 in | 1.6 in | ⚠️ 2.4× difference |
| Min. Group | 1+ | 1+ | See below |
| Min. Tank Size | 40 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Green Terror Cichlid — Aquarium species
The Green Terror Cichlid is a popular choice for experienced aquarists due to its striking appearance and vibrant colors. They are known for their aggression and should be kept in a species-specific tank. Their tall, laterally compressed bodies and vivid coloration make them visually appealing but require careful handling due to their potentially aggressive
→ Full Green Terror Cichlid care guide
Pajama Cardinalfish — Aquarium species
The Pajama Cardinalfish is a popular, beginner-friendly fish that can add a splash of color to your aquarium. They are generally peaceful and can be kept in a community tank. With moderate activity levels and a preference for undisturbed swimming spaces, they require a well-maintained water quality and a spacious tank.
Frequently Asked Questions
Can Green Terror Cichlid live with Pajama Cardinalfish?
Generally not recommended. Green Terror Cichlid and Pajama Cardinalfish are generally not recommended to be housed together. The issues listed above — whether water parameter incompatibility, predation risk, or aggression — create conditions where one or both fish are likely to suffer harm or chronic stress.
What tank size do I need for Green Terror Cichlid and Pajama Cardinalfish together?
A minimum of 40 gallons is recommended for keeping Green Terror Cichlid and Pajama Cardinalfish together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Green Terror Cichlid and Pajama Cardinalfish?
72–82°F
Is a Green Terror Cichlid aggressive toward a Pajama Cardinalfish?
Green Terror Cichlid is aggressive and Pajama Cardinalfish is semi. These animals require different water types and cannot share one aquarium.
Related Compatibility Guides
Compatibility score breakdown
The overall score is weighted across water chemistry, behavior, adult size, swimming zone, and social needs. A score is a planning aid—not a guarantee for individual fish.
| Factor | Score |
|---|---|
| Temperature | 100/100 |
| Ph | 0/100 |
| Temperament | 25/100 |
| Adult Size | 72/100 |
| Swim Zone | 68/100 |
| Social Needs | 92/100 |
Tank size scenarios
Use the scenario that matches the actual group sizes and temperament you plan to keep.
| Scenario | Tank | When it applies |
|---|---|---|
| Minimum viable | 53 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 75 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 100 gal | Best when keeping larger schools or reducing territorial pressure. |