Overview
The Blue Devil Damselfish (Chrysiptera cyanea) is a beginner saltwater species known for its electric blue coloration. Hardy but aggressive. Mid to Bottom.
Origin & Appearance
Origin: Indo-Pacific.
Colors: Electric Blue.
Body Shape: Deep Fusiform (oval/robust). Typical adult dimensions: 9.0 x 1.8 x 3.6.
Sexual Dimorphism: Minimal.
Tank & Water Requirements
| Min Tank Size | 20 gallons |
| Temperature | 75–79°F |
| pH Range | 8.1–8.4 |
| Water Hardness (GH) | dKH 8-12 |
| Bioload | low |
| Oxygen Demand | low |
| Plant Safe | yes |
| Aquarium Position | Mid to Bottom |
Behavior & Activity
Aggressive reef territorial swimmer; chases everything from its claimed rock; rapid darting attacks
Speed: 42/100Aggression: 6/10diurnal
Breeding
Moderate; egg depositor on rock
Common Diseases
💊 Hardy
Expert Notes
Hardy but aggressive