Blue Stripe Dwarf Parrot (Paracheilinus mccoskeri)

 

• Small fish safe: ✅ Yes (peaceful and non-aggressive)

• Small invert safe: ✅ Yes (reef-safe; does not harm invertebrates)

• Coral safe: ✅ Yes (does not harm corals)

• Minimum tank size: 208 liters (55 gallons)

• Adult size: Up to 8 cm (3 inches)

• Diet: Carnivorous, feeding on zooplankton and small meaty foods

• Be aware of: Requires a tightly sealed aquarium cover (prone to jumping); males may display increased coloration during courtship; best kept singly or in harems with one male and multiple females

 

Appearance and Coloration

The Blue Stripe Dwarf Parrotfish is renowned for its vibrant and dynamic coloration, especially evident in males:

• Males: Exhibit a predominantly red/orange body adorned with horizontal blue stripes and a yellow abdomen. The dorsal fin is orange with red, yellow, and blue accents, featuring a single elongated ray. The anal fin showcases a striking red band across its orange base. 

• Females: Display more subdued hues, lacking the pronounced fin extensions and vivid patterns seen in males.

Males intensify their coloration during courtship displays, “flashing” their fins to attract females. 

 

Natural Habitat and Behavior

Native to the Indo-Pacific region, Paracheilinus mccoskeri inhabits reef slopes and rubble zones, often swimming near the bottom. In the wild, they form small groups where a male swims back and forth between groups of females. 

 

Tank Requirements and Water Parameters

• Minimum Tank Size: 208 liters (55 gallons)

• Water Parameters:

• Temperature: 22°C – 26°C (72°F – 78°F)

• pH: 8.1 – 8.4

• Specific Gravity: 1.020 – 1.025

• Aquascaping:

• Provide ample live rock to offer hiding spots and mimic natural reef structures.

• Ensure open swimming areas to accommodate their active nature.

• Lighting: Moderate to high, replicating natural reef conditions.

• Water Movement: Moderate, simulating their natural habitat.

Note: A tightly fitting lid is essential, as McCosker’s Flasher Wrasses are known jumpers. 

 

Diet and Feeding

In their natural habitat, Blue stripe dwarf parrots feed on zooplankton. In captivity, they adapt well to a variety of meaty foods.

• Captive Diet:

• Offer vitamin-enriched frozen mysis shrimp and brine shrimp.

• Provide high-quality marine flake and pellet foods.

Feeding Frequency: Multiple small feedings throughout the day to mimic their natural feeding habits. 

 

Compatibility and Social Structure

• Temperament:

• Generally peaceful and suitable for community aquariums.

• Males may display increased coloration and fin “flashing” during courtship.

• Tank Mates:

• Compatible with other non-aggressive species such as gobies, blennies, and dwarf angelfish.

• Avoid housing with aggressive or significantly larger species that may intimidate or outcompete them.

• Social Structure:

• Best kept singly or in harems with one male and multiple females.

• Introducing multiple males in the same tank can lead to aggression unless the aquarium is sufficiently large.

 

Important Considerations

• Jumping Behavior: Ensure the aquarium has a secure lid, as these wrasses are prone to leaping out of tanks.

• Acclimation: Introduce them to well-established aquariums with stable water parameters to reduce stress.

• Behavioral Displays: Males exhibit vibrant “flashing” displays during courtship, enhancing the visual appeal of the aquarium.