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Pajama Cardinalfish


Pajama Cardinalfish, Sphaeramia nematoptera

The Pajama Cardinal is also known as the Polka-dot Cardinalfish, the Spotted Cardinalfish, the Coral Cardinalfish, and the Red Spotted Cardinal. It comes from the Indo- Pacific. It has two distinctive dorsal fins, typical of cardinalfish. The name "cardinal" refers to the fact that many of this species are red, although yellow and silver are probably more predominate colors. The Pajama Cardinal has a green / yellow face and a dark band running from the first dorsal fin to the pectoral fin. The back half of the body is silver, with red/orange dots, giving it the appearance of polka-dot pajamas. The fins at the back half of the body are fringed in white. Pajama Cardinals are nocturnal and therefore have very large eyes.

Pajama Cardinals are an excellent choice for the beginning saltwater aquarist and they are almost as popular as the Banggai Cardinal. They transport well, are inexpensive and adapt well to aquarium life. They can also be bred in captivity, so tank raised specimens may be available. They should have a tank of at least 40 gallons with rocky areas, caves and medium lighting. Pajama Cardinals swim slowly and usually do not shy away from spectators. 

Pajama Cardinalfish Sphaeramia nematoptera

During the day, Pajama Cardinals tend to hover in groups in one place and like to remain stationary under rock ledges. In the wild they hide among sea urchin spines when they are threatened. Anything that simulates this arrangement is a useful addition to the tank. At night, Pajama Cardinals become solitary and hunt for food, covering the same feeding patterns that damsels do during the day. This has given them the title of damsel of the night. Pajama Cardinalfish Sphaeramia nematoptera

The Pajama Cardinalfish is not aggressive toward other fish or corals, so they are great choices for a community tank. They will establish a hierarchy among their own kind but do not display aggressive behaviour. The only issue is to ensure they are not picked on by other species. Suitable tank mates include other Cardinalfish, Blennies, Clowns, Damsels, Small Angels, Gobies, Hawkfish and Tangs. Cardinalfish are prey for larger species. Pajama Cardinals may bother small invertebrates in a reef tank though. The Pajama Cardinalfish should be given a well balanced diet consisting of mysis shrimp, brine shrimp, flaked foods, pellet foods, chopped fish, chopped clams and bloodworms. In the wild, they feed on plankton. 

There are no significant or distinctive characteristics differentiating males from females, though females may be somewhat larger than males. Cardinalfish are mouth-brooders. The male will incubate the fertilized eggs in its mouth. Pajama Cardinals have been bred in captivity, but not as extensively as the Banggai Cardinal. Water temperatures should be raised a couple of degrees to induce breeding. The eggs hatch after a week. 

Scientific Name: Sphaeramia nematoptera
Family: Apogonidae
Care: Easy
Temperature: 22 - 26 C; 72 - 79 F
pH: 8.1 - 8.4
dH: 8 - 12
Specific Gravity: 1.020 - 1.025
Size: 8 cm; 3 inches
Breeding: Mouth Brooder
Life Span: years
Crustacean Safe: No
Coral Safe: Yes


Cardinalfish, Blennies, Clowns, Damsels, Small Angels, Gobies, Hawkfish and Tangs