Description
Pajama Cardinalfish (Sphaeramia nematoptera)
Overview
The Sphaeramia nematoptera, widely known as the Pajama Cardinalfish, is a popular, hardy, and distinctively patterned marine fish. Named for the spotted “pajama-like” pattern on its posterior and its bright, contrasting colors, it is a favorite for both community and nano reef tanks due to its peaceful nature.
- Temperament: Peaceful and slow-moving.
- Size: Grows to approximately 7–8 cm.
- Key Trait: Nocturnal by nature, though they readily adapt to daylight hours in the aquarium. They are often seen hovering in the water column in small groups.
- Hardiness: Excellent; they are considered one of the best “beginner-friendly” marine fish.
Care Requirements
- Tank Size: Minimum 120 litres. While they don’t require vast swimming space, they appreciate areas to hover.
- Environment: They are shy and require a tank with plenty of live rock, caves, and overhangs where they can retreat if they feel threatened. They are not active swimmers and prefer calm water flow.
- Lighting: They prefer lower-light environments and may hide if the tank lighting is exceptionally intense.
- Water Parameters:
- Temperature: 22–26°C.
- Salinity: 1.020–1.025 SG.
- pH: 8.1–8.4.
Maintenance
- Water Quality: They are relatively hardy but thrive best in stable conditions. Maintain low nitrates (<20 ppm).
- Routine: Regular 10–20% water changes are sufficient.
- Equipment: A standard filtration system is fine, provided there is enough rockwork for them to feel secure.
Diet
- Type: Carnivore/Planktivore.
- Staples: In the aquarium, they accept a wide range of meaty foods. Offer frozen Mysis shrimp, brine shrimp, finely chopped seafood, and high-quality marine pellets.
- Feeding Habits: They have relatively large mouths for their size and can easily consume standard frozen preparations. They are not fast swimmers, so ensure they have enough time to eat if housed with more aggressive feeders.
Behavior and Compatibility
- Social: Very peaceful. Best kept in small groups (3+) if the tank size allows, as they exhibit interesting social behaviors within a school.
- Tankmates: Perfect for peaceful community tanks. They can be kept with gobies, blennies, small wrasses, and other non-aggressive fish.
- Avoid: Keep away from large, highly aggressive, or predatory fish that might harass or consume them.
- Reef Safety: Completely reef-safe. They will not bother corals, sessile invertebrates, or mobile invertebrates like cleaner shrimp.
Reproduction
- They are mouthbrooders—the male carries the eggs in his mouth for several days until they hatch.
- Captivity: Breeding is possible in home aquaria. When a pair is bonded and healthy, the male will gather the egg clutch from the female. Rearing the fry is a significant project requiring a separate nursery tank and a constant supply of live rotifers and copepods.
Tips
- Schooling Behavior: While they are peaceful, they are most comfortable and visually striking when kept in a small group.
- Acclimation: They are generally resilient, but as with all new arrivals, a quarantine period is recommended to ensure they are eating well.
- Feeding: Since they are nocturnal, you may find them more active during evening feedings or when the aquarium lights are dimmed.
- Peaceful Addition: If you are looking to add a splash of color to a calm, peaceful reef tank, the Pajama Cardinalfish is an excellent choice.
Picture for illustrative purposes only. Either come in store to view available stock or request pictures to be sent to you.
Please Note: Due to variations within species resulting from age, region, sex, etc., the actual livestock may not look identical to the image. Approximate size range may also vary between individual specimens.
