Compatibility Overview
Diamond Tetra and Flame Angelfish 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 | Diamond Tetra | Flame Angelfish | Verdict |
|---|---|---|---|
| Temperature | 72–82°F | 75–81°F | ✅ 75–81°F |
| pH Range | 6.0–7.5 | 8.0–8.3 | ❌ No overlap |
| Temperament | semi | semi | ⚠️ Monitor |
| Adult Size | 1.2 in | 2.8 in | ⚠️ 2.3× difference |
| Min. Group | 6+ | 1+ | See below |
| Min. Tank Size | 55 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
Diamond Tetra — Aquarium species
The Diamond Tetra is a popular freshwater fish known for its vibrant colors and peaceful nature. It is well-suited for community tanks and can thrive in a variety of water conditions. With a moderate activity level and a preference for schools, this species is a great addition to any beginner or intermediate aquarist's tank.
→ Full Diamond Tetra care guide
Flame Angelfish — Aquarium species
The Flame Angelfish is a popular choice for saltwater aquariums due to its vibrant coloration and peaceful nature. It requires a spacious tank with plenty of swimming space and a stable water environment. With proper care, it can thrive in a community tank with compatible species.
Frequently Asked Questions
Can Diamond Tetra live with Flame Angelfish?
Generally not recommended. Diamond Tetra and Flame Angelfish 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 Diamond Tetra and Flame Angelfish together?
A minimum of 55 gallons is recommended for keeping Diamond Tetra and Flame Angelfish together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Diamond Tetra and Flame Angelfish?
75–81°F
Is a Diamond Tetra aggressive toward a Flame Angelfish?
Diamond Tetra is semi and Flame Angelfish 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 | 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. |