Pajama Cardinal

Pajama Cardinalfish - Whimsical Pattern and Peaceful Personality

The Pajama Cardinalfish (Sphaeramia nematoptera), also known as the Spotted Cardinalfish or Polka Dot Cardinalfish, is one of the most uniquely patterned and charming fish available to reef keepers. Named for its distinctive "pajama-like" appearance with contrasting sections of color and bold polka dots, this peaceful schooling fish brings both visual interest and entertaining group behavior to any reef aquarium.

Key Features:

• Distinctive Pattern: Unique three-section coloration—yellow-green front, black mid-section band, and silver rear with bold red-orange polka dots
• Schooling Behavior: Can be kept in groups, displaying natural schooling behavior that's fascinating to observe
• Peaceful Temperament: Extremely peaceful with all tank mates, making them ideal community fish
• Reef Safe: Completely safe with all corals and most invertebrates
• Hardy & Adaptable: Captive-bred for superior health and easy acclimation to aquarium life
• Beginner Friendly: Easy to care for and readily accepts a variety of foods
• Nocturnal Activity: Most active during dawn, dusk, and nighttime hours

Care Requirements:

Tank Size: Minimum 30 gallons; 50+ gallons recommended for groups
Diet: Carnivore - readily accepts frozen mysis shrimp, brine shrimp, and quality pellets
Temperament: Peaceful with all species; thrives in groups of 3 or more
Reef Compatibility: Excellent - will not harm corals; may eat very small ornamental shrimp
Experience Level: Beginner to Advanced - suitable for all skill levels
Adult Size: 3-4 inches maximum

Unique Appearance:

The Pajama Cardinalfish has one of the most distinctive and whimsical patterns in the marine aquarium hobby:

• Front Section: Yellow-green to olive coloration on the head and front body
• Mid-Section: Bold vertical black band across the middle of the body
• Rear Section: Silver-white background covered with large red-orange polka dots
• Large Eyes: Prominent eyes adapted for low-light conditions
• Forked Tail: Distinctive forked caudal fin with red-orange spots

Schooling Behavior:

One of the most appealing aspects of Pajama Cardinalfish is their natural schooling behavior. When kept in groups of 3 or more, they'll form loose schools and swim together, especially during feeding time or when they feel secure. This group behavior is entertaining to watch and brings natural reef dynamics to your aquarium. Groups of 5-7 fish create the most impressive displays in larger tanks.

Nocturnal Nature:

Pajama Cardinals are primarily nocturnal or crepuscular (most active at dawn and dusk). During the day, they may rest in caves or among rockwork, becoming more active as evening approaches. Don't be concerned if they're less active during bright daylight hours—this is completely natural behavior. They'll emerge for feeding and become more animated during lower light periods.

Feeding:

Pajama Cardinalfish are easy to feed and readily accept a variety of foods. Offer frozen mysis shrimp, brine shrimp, and quality carnivore pellets 1-2 times daily. They have relatively small mouths, so ensure food is appropriately sized. Feed during evening hours or just after lights-on in the morning when they're most active. A varied diet maintains their vibrant coloration and supports optimal health.

Compatibility:

Pajama Cardinals are among the most peaceful fish available and can be kept with virtually any tank mates, including:

• Other peaceful cardinalfish (including their own species)
• Clownfish, gobies, blennies, dartfish, and other peaceful community fish
• All types of corals, including delicate soft corals and LPS
• Most invertebrates (may eat very small ornamental shrimp like sexy shrimp)

Avoid housing with aggressive fish or large predators. Their slow, deliberate swimming makes them vulnerable to harassment from aggressive species.

Tank Setup:

Provide plenty of caves, overhangs, and hiding spots where Pajama Cardinals can retreat during the day. They appreciate rockwork with multiple hiding places and will establish favorite resting spots. Moderate to low lighting is preferred, though they'll adapt to brighter systems. Gentle to moderate water flow is ideal, as they're not strong swimmers and prefer calmer areas of the tank.

Mouth Brooding Behavior:

Pajama Cardinals are mouth brooders—males incubate eggs in their mouths until they hatch. If you keep a group, you may observe this fascinating reproductive behavior. A male carrying eggs will have a visibly swollen mouth and may refuse food during the incubation period (typically 7-10 days). This is completely normal and the male will resume eating once the fry are released.

Group Recommendations:

While Pajama Cardinals can be kept individually, they truly shine when kept in groups:

• Single Fish: Will do fine but may be shy
• Pair (2 fish): Good option for smaller tanks
• Small Group (3-5 fish): Ideal for 30-50 gallon tanks; displays natural behavior
• Large Group (6+ fish): Best for 75+ gallon tanks; creates impressive schooling displays

Captive-Bred Advantage:

All our Pajama Cardinalfish are captive-bred, ensuring superior health, disease resistance, and adaptability to aquarium conditions. Captive breeding also protects wild reef populations while providing you with hardier, more resilient fish that are already acclimated to prepared foods and aquarium life.

Our Pajama Cardinalfish are carefully selected, quarantined, and eating well before shipment. Each fish is backed by our live arrival guarantee, ensuring your whimsically patterned new addition arrives healthy and ready to bring peaceful charm and entertaining group behavior to your reef aquarium.