Compatibility Overview
Glass Catfish 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 | Glass Catfish | Pajama Cardinalfish | Verdict |
|---|---|---|---|
| Temperature | 72–82°F | 72–82°F | ✅ 72–82°F |
| pH Range | 6.5–7.5 | 8.0–8.3 | ❌ No overlap |
| Temperament | semi | semi | ⚠️ Monitor |
| Adult Size | 3.9 in | 1.6 in | ⚠️ 2.4× difference |
| Min. Group | 6+ | 1+ | See below |
| Min. Tank Size | 55 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Glass Catfish — Aquarium species
The Glass Catfish, Kryptopterus vitreolus, is a popular freshwater aquarium fish known for its unique, translucent body and iridescent scales. It is a peaceful species that thrives in groups and is suitable for beginners due to its hardy nature. These catfish are bottom-dwellers and require a well-decorated tank with plenty of swimming space. They are sensit
→ Full Glass Catfish 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 Glass Catfish live with Pajama Cardinalfish?
Generally not recommended. Glass Catfish 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 Glass Catfish and Pajama Cardinalfish together?
A minimum of 55 gallons is recommended for keeping Glass Catfish and Pajama Cardinalfish together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Glass Catfish and Pajama Cardinalfish?
72–82°F
Is a Glass Catfish aggressive toward a Pajama Cardinalfish?
Glass Catfish is semi 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 | 62/100 |
| Adult Size | 72/100 |
| Swim Zone | 92/100 |
| 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 | 55 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 | 125 gal | Best when keeping larger schools or reducing territorial pressure. |