Description

🐟 Blue Green Chromis — Description & Care Guide

📌 Scientific Name: Chromis viridis

📌 Common Names: Blue Green Chromis, Green Chromis, Reef Chromis

📌 Origin: Indo-Pacific — found in lagoons and coral reefs from East Africa to Australia and Japan

📌 Type: Saltwater Damselfish (peaceful species)

🔍 Description

• Color: Iridescent blue-green body that shifts shades under lighting.

• Size: Grows up to 3 inches (7.5 cm).

• Body Shape: Oval, laterally compressed with a forked tail; streamlined for quick swimming.

• Lifespan: Typically 5–8 years in captivity with good care.

🧪 Aquarium Care

🏠 Tank Size

• Minimum: 30 gallons (114 liters) for a small group

• Best kept in groups of 3–6+ in tanks 55+ gallons to encourage natural schooling behavior and reduce aggression.

🌡️ Water Parameters

• Temperature: 72–78°F (22–26°C)

• pH: 8.1–8.4

• Salinity: 1.023–1.025 SG

• Ammonia/Nitrite: 0 ppm — very sensitive to water quality in groups

🧬 Behavior & Temperament

• Temperament: Peaceful — one of the calmest damselfish.

  • Can sometimes become slightly aggressive toward each other if kept in small numbers.

• Reef-Safe: ✅ Yes — totally safe with corals and invertebrates.

• Schooling: Best kept in odd-numbered groups (3, 5, 7) to reduce aggression.

• Activity: Very active swimmers; spend most time in open water near the top or middle of the tank.

🍽️ Diet & Feeding

• Type: Omnivore

• Eats:

  • Frozen mysis and brine shrimp

  • Marine pellets and flakes

  • Copepods and fine plankton

  • Occasional nori/algae-based foods

• Feeding Frequency: 2–3 times per day (small amounts)

🪸 Tank Setup

• Provide:

  • Open swimming space — they are open-water swimmers

  • Some live rock for retreat/hiding

  • Moderate flow — mimics their natural reef environment

✅ Pros

• Very hardy and beginner-friendly

• Peaceful and community tank compatible

• Active swimmers and visually appealing in groups

• Reef-safe with corals and shrimp

⚠️ Cautions

• Group size matters: Small groups (2–3) may lead to bullying or one fish getting picked on

• Tank mates: Avoid very aggressive species; Chromis may be shy around larger, dominant fish

• Long-term care: Despite being hardy, they are prone to stress-related diseases if overcrowded or housed with nippy tankmates