McCosker's Flasher Wrasse

The McCosker’s Flasher Wrasse (Paracheilinus mccoskeri) is one of the most visually impressive reef fish, famous for the male’s dramatic “flashing” displays where it rapidly shows off its bright red, orange, and blue coloration. This behavior is used for courtship and social interaction, making it a fascinating fish to observe.

Native to the Indo-Pacific region, this wrasse is commonly found in reef slopes and lagoon environments, where it actively swims in the water column.

Key Features:

• Stunning flashing color displays in males
• Peaceful and highly active swimmer
• One of the most popular flasher wrasses in the hobby
• Adds constant movement and color to reef tanks

Feeding:

• Carnivorous species
• Feeds on zooplankton, mysis shrimp, brine shrimp, and frozen foods
• Accepts high-quality marine pellets
• Requires frequent small feedings

Care Requirements:

• Minimum tank size: 120–150L+
• Secure lid required (strong jumper)
• Open swimming space with live rock for shelter
• Best in peaceful, mature reef aquariums

Compatibility:

• Fully reef safe
• Safe with corals and invertebrates
• Peaceful toward most tank mates
• May be shy at first until fully acclimated

Pro Tips:

• Keep in calm community reef setups
• Feed small portions multiple times daily
• Can be kept in harems (1 male + females) in larger tanks
• Provide shaded resting areas among rockwork