Compatibility Overview
Harlequin Rasbora and Severum Cichlid 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 55-gallon tank is recommended to provide adequate territory and water volume for both species.
| Factor | Harlequin Rasbora | Severum Cichlid | Verdict |
|---|---|---|---|
| Temperature | 72–81°F | 75–82°F | ✅ 75–81°F |
| pH Range | 5.5–7.5 | 6.0–7.5 | ✅ 6.0–7.5 |
| Temperament | peaceful | semi | ⚠️ Monitor |
| Adult Size | 1.75 in | 2.4 in | ✅ Similar |
| Min. Group | 8+ | 1+ | See below |
| Min. Tank Size | 55 gallons (for both species) | — | |
✅ Compatibility Positives
⚠️ Caution Points
Species Profiles
Harlequin Rasbora — Trigonostigma heteromorpha
Active mid-level schooling fish with a distinctive black triangular patch. One of the best all-around community tank fish.
→ Full Harlequin Rasbora care guide
Severum Cichlid — Aquarium species
The Severum Cichlid, known for its vibrant colors and peaceful nature, is a popular choice for freshwater aquariums. They have a lifespan of around 5 years and require a minimum tank size of 80 liters. These fish are not schooling fish but are known to be gentle and compatible with a variety of tank mates. Their tall, laterally compressed body shape makes th
Frequently Asked Questions
Can Harlequin Rasbora live with Severum Cichlid?
Yes, in a well-planned setup. Harlequin Rasbora and Severum Cichlid 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 55-gallon tank is recommended to provide adequate territory and water volume for both species.
What tank size do I need for Harlequin Rasbora and Severum Cichlid together?
A minimum of 55 gallons is recommended for keeping Harlequin Rasbora and Severum Cichlid together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Harlequin Rasbora and Severum Cichlid?
75–81°F
Is a Harlequin Rasbora aggressive toward a Severum Cichlid?
Harlequin Rasbora is peaceful and Severum Cichlid is semi. 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 | 86/100 |
| Ph | 100/100 |
| 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 | 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. |