Compatibility Overview
Bolivian Ram and Cardinal Tetra can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges, and neither poses a major aggression risk to the other. A minimum 40-gallon tank is recommended to provide adequate territory and water volume for both species.
| Factor | Bolivian Ram | Cardinal Tetra | Verdict |
|---|---|---|---|
| Temperature | 72–82°F | 73–82°F | ✅ 73–82°F |
| pH Range | 6.5–7.5 | 4.5–7.0 | ⚠️ 6.5–7.0 (narrow) |
| Temperament | semi | peaceful | ⚠️ Monitor |
| Adult Size | 2.0 in | 1.5 in | ✅ Similar |
| Min. Group | 1+ | 6+ | See below |
| Min. Tank Size | 40 gallons (for both species) | — | |
✅ Compatibility Positives
⚠️ Caution Points
Species Profiles
Bolivian Ram — Aquarium species
The Bolivian Ram is a popular freshwater fish known for its vibrant colors and peaceful nature. They are well-suited for community tanks with other peaceful species. These fish are relatively easy to care for, making them a great choice for beginners. They require a well-maintained tank with a moderate water flow and plenty of space for swimming.
→ Full Bolivian Ram care guide
Cardinal Tetra — Paracheirodon axelrodi
Brilliant red-and-blue schooling fish from the Rio Negro. Prefers soft, acidic, warm water — a natural companion for discus.
Frequently Asked Questions
Can Bolivian Ram live with Cardinal Tetra?
Yes, in a well-planned setup. Bolivian Ram and Cardinal Tetra can generally share an aquarium with appropriate planning. Both species prefer overlapping temperature and pH ranges, and neither poses a major aggression risk to the other. A minimum 40-gallon tank is recommended to provide adequate territory and water volume for both species.
What tank size do I need for Bolivian Ram and Cardinal Tetra together?
A minimum of 40 gallons is recommended for keeping Bolivian Ram and Cardinal Tetra together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Bolivian Ram and Cardinal Tetra?
73–82°F
Is a Bolivian Ram aggressive toward a Cardinal Tetra?
Bolivian Ram is semi and Cardinal Tetra is peaceful. No major aggression issues are expected between these species.
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 | 50/100 |
| Temperament | 75/100 |
| Adult Size | 100/100 |
| 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 | 40 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 55 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 90 gal | Best when keeping larger schools or reducing territorial pressure. |