Compatibility Overview
Discus and Green Terror Cichlid can potentially coexist, but the combination requires careful attention. Some combination of water parameter differences, size mismatch, or temperament issues make this pair challenging. A larger tank (minimum 100 gallons), dense planting, and close monitoring are essential.
| Factor | Discus | Green Terror Cichlid | Verdict |
|---|---|---|---|
| Temperature | 82–88°F | 72–82°F | ⚠️ 82–82°F (narrow) |
| pH Range | 5.0–7.0 | 6.0–8.0 | ✅ 6.0–7.0 |
| Temperament | semi | aggressive | ❌ Risk |
| Adult Size | 8 in | 3.9 in | ⚠️ 2.1× difference |
| Min. Group | 5+ | 1+ | See below |
| Min. Tank Size | 100 gallons (for both species) | — | |
✅ Compatibility Positives
⚠️ Caution Points
Species Profiles
Discus — Symphysodon spp.
The 'king of the aquarium' — beautiful but demanding. Requires very warm, soft, acidic water that excludes most community fish.
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
Frequently Asked Questions
Can Discus live with Green Terror Cichlid?
With significant caution and a larger tank. Discus and Green Terror Cichlid can potentially coexist, but the combination requires careful attention. Some combination of water parameter differences, size mismatch, or temperament issues make this pair challenging. A larger tank (minimum 100 gallons), dense planting, and close monitoring are essential.
What tank size do I need for Discus and Green Terror Cichlid together?
A minimum of 100 gallons is recommended for keeping Discus and Green Terror Cichlid together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Discus and Green Terror Cichlid?
82–82°F (narrow)
Is a Discus aggressive toward a Green Terror Cichlid?
Discus is semi and Green Terror Cichlid is aggressive. Their preferred temperature ranges have little or no safe overlap.
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 | 0/100 |
| Ph | 50/100 |
| 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 | 100 gal | Only for the recommended minimum groups, mature filtration, and close monitoring. |
| Recommended community | 150 gal | Adds territory, swimming room, and a safer buffer for behavior. |
| Low-conflict setup | 220 gal | Best when keeping larger schools or reducing territorial pressure. |