Compatibility Overview
Flame Angelfish and Rainbow Shark 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 | Flame Angelfish | Rainbow Shark | Verdict |
|---|---|---|---|
| Temperature | 75–81°F | 72–79°F | ✅ 75–79°F |
| pH Range | 8.0–8.3 | 6.5–7.5 | ❌ No overlap |
| Temperament | semi | semi | ⚠️ Monitor |
| Adult Size | 2.8 in | 6 in | ⚠️ 2.1× difference |
| Min. Group | 1+ | 1+ | See below |
| Min. Tank Size | 55 gallons (for both species) | — | |
✅ Compatibility Positives
❌ Incompatibility Reasons
Species Profiles
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.
→ Full Flame Angelfish care guide
Rainbow Shark — Epalzeorhynchos frenatum
Active bottom dweller that becomes territorial at maturity. One per tank; avoid other shark-like or bottom-dwelling species.
Frequently Asked Questions
Can Flame Angelfish live with Rainbow Shark?
Generally not recommended. Flame Angelfish and Rainbow Shark 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 Flame Angelfish and Rainbow Shark together?
A minimum of 55 gallons is recommended for keeping Flame Angelfish and Rainbow Shark together. A larger tank improves water stability and reduces territorial conflict.
What temperature suits both Flame Angelfish and Rainbow Shark?
75–79°F
Is a Flame Angelfish aggressive toward a Rainbow Shark?
Flame Angelfish is semi and Rainbow Shark 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 | 67/100 |
| 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 | 100 gal | Best when keeping larger schools or reducing territorial pressure. |