The Pajama Cardinalfish is a rainbow of playful colors. It has a greenish-yellow face, bright orange eyes, and a silver-based body dressed with a bold black scalar margin and a posterior dotted with orange polka-dots. Though its bold coloration may stand out, Sphaeramia nematoptera has a peaceful nature that lets it blend perfectly into any community saltwater aquarium.
For the best care, the Pajama Cardinalfish should be kept in small schools in suitably sized aquariums of at least 30 gallons. Because the Pajama Cardinalfish is a slow and methodical swimmer, it should be housed with peaceful tankmates and offered a plethora of hiding places amongst rockwork or plants. Most Pajama Cardinalfish will tend to hide in sea grass or other plants. Some may also camouflage themselves against long spined sea urchins.
Like many other schooling fish, the Pajama Cardinalfish will form a strict hierarchy when kept in small groups within the aquarium. However, unlike some social fish, this member of the Apogonidae family does not use aggression to exert dominance over other cardinalfish.
The Pajama Cardinalfish requires a well balanced diet of meaty foods such as feeder shrimp, flake foods, pellet foods, marine flesh, bloodworms, and depending on its size, live feeder fish.