Black Bar Chromis

Black Bar Chromis Overview

• Common Name: Black Bar Chromis

• Scientific Name: Chromis retrofasciata

• Family: Pomacentridae (same as clownfish and other damselfish)

• Origin: Western Pacific – including Indonesia, Papua New Guinea, and the Great Barrier Reef

• Size: Up to 2.5 inches (6.5 cm)

• Lifespan: 5–8 years with proper care

🌈 Appearance

• Body Color: Yellow to yellowish-white body with a prominent vertical black bar running behind the eyes (hence the name “black bar”)

• Fins: Often semi-transparent with slight yellow or white hues

• Shape: Typical chromis/damselfish shape – small, oval, and laterally compressed

🏝️ Natural Habitat

• Found on outer reef slopes, lagoons, and coral-rich areas

• Lives in small to medium schools, often near branching coral heads (especially Acropora)

🐠 Aquarium Care

Tank Requirements:

• Minimum Tank Size: 30 gallons for a small group (larger is better for schooling)

• Best Setup:

  • Plenty of live rock for shelter and grazing

  • Open swimming space

  • Gentle to moderate water flow

Water Parameters:

• Temperature: 72–78°F (22–26°C)

• pH: 8.1–8.4

• Salinity: 1.020–1.025

• Ammonia/Nitrites: 0 ppm

• Nitrates: <20 ppm preferred

🍽️ Diet

• Feeding Type: Omnivore

• Diet:

  • Frozen mysis and brine shrimp

  • High-quality marine pellets and flakes

  • Enriched zooplankton or copepods

  • Occasional algae-based foods or spirulina

• Feeding Frequency: 1–2 times daily

• Not picky eaters — very easy to feed

🤝 Behavior & Compatibility

• Temperament: Generally peaceful

• Schooling Behavior: Best kept in odd-numbered groups (3, 5, or more) to minimize hierarchy aggression

• Aggression: Can be a little pushy with conspecifics or smaller peaceful fish in tight spaces, but usually calm

• Reef Safe: ✅ Yes — won’t harm corals or inverts

• Good Tankmates:

  • Clownfish

  • Gobies

  • Cardinalfish

  • Wrasses

  • Tangs

  • Other peaceful to semi-aggressive reef fish

✅ Pros

• Attractive and distinctive coloration

• Hardy and beginner-friendly

• Peaceful and reef safe

• Active swimmers — add life and movement to the tank

• Compatible with many common community fish

❌ Cons

• Can show intra-species aggression in small tanks or pairs

• Less colorful than some other chromis species

• May fade in color slightly with age or poor diet

💡 Tips for Success

• Keep in small odd-numbered groups (3–7) in tanks over 30–40 gallons

• Use plenty of rockwork with caves and hiding spots

• Supplement with vitamin-enriched foods to keep color vibrant

• Monitor group dynamics — if one fish becomes overly dominant, it may need to be removed

Summary