Pajama Cardinal (Captive Bred) 

Also known as Spotted Cardinalfish, Polkadot Cardinalfish

The Pajama Cardinal is a charming and distinctive species displaying a unique color pattern that resembles pajamas, with a yellow-green front, dark vertical band at mid-body, and white rear covered in orange-red spots. This hardy and peaceful cardinalfish is an excellent choice for beginners and thrives in groups.

Key Features

• Scientific Name: Sphaeramia nematoptera
• Common Names: Pajama Cardinalfish, Spotted Cardinalfish, Polkadot Cardinalfish
• Adult Size: Up to 3.5 inches
• Lifespan: 3-5 years with proper care
• Temperament: Very peaceful and social; does best in groups
• Reef Compatibility: Completely reef safe; will not harm corals or invertebrates
• Minimum Tank Size: 30 gallons minimum; 40+ gallons preferred for groups
• Experience Level: Beginner; extremely hardy and easy to maintain

Habitat & Tank Requirements

• Tank Environment: Provide abundant hiding places with live rock, caves, and sheltered areas. This species forms loose aggregations and appreciates multiple retreat spots. Prefers areas with gentle water flow.
• Water Parameters:
  • Temperature: 72-78°F (22-26°C)
  • Salinity: 1.020-1.025
  • pH: 8.1-8.4
  • Very tolerant of typical reef conditions
• Equipment Recommendations:
  • Standard filtration system
  • Protein skimmer
  • Gentle to moderate water circulation These maintain healthy conditions for this adaptable species.

Diet & Feeding 

Pajama Cardinals are carnivores with excellent appetites. Recommended foods include:

• Staples: High-quality marine pellets, carnivore pellets
• Frozen Foods: Mysis shrimp, brine shrimp, cyclops, copepods, finely chopped seafood
• Live Foods: Live brine shrimp (rarely necessary; readily accepts frozen)
• Feeding Frequency: Once or twice daily
• Special Note: Extremely easy to feed; accepts virtually all meaty foods

Social Structure & Group Dynamics

• Best Kept in Groups: Naturally schools; 3-6+ individuals create natural behavior
• Pairing Behavior: Will pair off for breeding within groups
• Very Peaceful: Non-aggressive toward all tankmates including conspecifics
• Introduce Simultaneously: Groups establish better when added together

Notes & Considerations

• One of the hardiest and most beginner-friendly marine fish available.
• Captive-bred specimens are widely available, hardy, and already adapted to aquarium foods.
• The distinctive “pajama” pattern makes them instantly recognizable and endearing.
• Males are mouth-brooders and may breed readily in home aquariums.
• Primarily nocturnal but will be active during the day, especially at feeding time.
• Slow-moving and peaceful; ensure they receive adequate food in tanks with aggressive feeders.
• Often forms tight groups during the day, spreading out at night to feed.
• Excellent for peaceful community reef tanks and suitable for nano aquariums.
• Very hardy and disease-resistant, especially captive-bred specimens.
• Generally hovers near caves or under ledges during the day.
• Does not require special lighting or water flow conditions.

Why Choose a Quarantined Pajama Cardinal (Captive Bred)? 

Purchasing a quarantined, captive-bred specimen from us means you’re starting with a healthier, better-acclimated fish that has never known the stress of wild collection. All fish are observed, treated as needed, and conditioned to accept prepared foods before sale, giving you a stronger chance of long-term success with this delightful and easy-to-keep species.