Yellow Lined Cardinalfish - Ostorhinchus cyanosoma

Yellow Lined Cardinalfish (Ostorhinchus cyanosoma)

The Yellow Lined Cardinalfish, Ostorhinchus cyanosoma, is a peaceful, attractive marine cardinalfish with a silvery-blue to pale body and bright yellow-orange horizontal stripes. Also known as the Yellowstriped Cardinalfish, Goldline Cardinalfish or Orange-lined Cardinalfish, this Indo-Pacific species is a superb choice for calm reef aquariums where a small group can hover together around ledges, caves and shaded rockwork. It is reef safe, modest in size and generally easy to feed, but it does best in peaceful aquariums with plenty of shelter and low aggression.

Common Name:
Yellow Lined Cardinalfish, Yellow-lined Cardinalfish, Yellowstriped Cardinalfish, Yellow Striped Cardinalfish, Goldline Cardinalfish, Gold-striped Cardinalfish, Orange-lined Cardinalfish.

Scientific Name (Latin):
Ostorhinchus cyanosoma
Formerly known as Apogon cyanosoma.

Maximum Size:
Usually around 6 cm, with larger specimens reaching up to around 8 cm.

Water Type:
Marine

Origin / Natural Habitat:
Indo-Pacific, including the Red Sea and East Africa across the Indian Ocean and western Pacific to northern Australia, New Caledonia, the Ryukyu Islands and surrounding reef regions. Naturally found in sheltered clear-water areas of lagoon reefs and seaward reefs, often under ledges, inside holes or among the long spines of sea urchins, at depths from around 1–50 m.

Water Parameters:
Temperature: 24–27°C
pH Range: 8.1–8.4
Hardness or Salinity: SG 1.020–1.025

Temperament:
Peaceful and social. Best kept with calm reef-safe fish that will not bully it or outcompete it at feeding time. It is usually more confident in a small group and may become shy if kept singly in a busy aquarium. Avoid large predatory fish and highly aggressive tank mates.

Diet:
Carnivorous planktivore and small-invertebrate feeder. In the wild, it feeds on planktonic crustaceans and small invertebrates. In the aquarium, offer frozen mysis, enriched brineshrimp, cyclops, copepods, finely chopped krill, calanus, quality marine micro pellets and finely chopped meaty foods. Small regular feeds are ideal, with occasional evening feeding useful because cardinalfish are naturally more active at dusk and after dark.

Minimum Tank Size:
A minimum of 120 litres is recommended for a small group, with larger aquariums preferred for stable shoals and mixed reef communities. Although small, this species benefits from open hovering space as well as shaded retreats.

Behaviour & Activity:
A gentle shoaling cardinalfish that often hovers in loose groups beneath ledges, around caves, under overhangs or near branching coral and urchin-like shelter. It is naturally crepuscular to nocturnal, but settled aquarium specimens will usually become visible during the day in peaceful systems. Provide shaded areas, caves, overhangs and moderate flow so the group can rest securely and feed confidently.

Reef Safe:
Reef Safe
Safe with corals and most ornamental invertebrates. It does not nip corals and is well suited to peaceful reef aquariums. Very tiny shrimps, larvae or small worms may be eaten as part of its natural diet, so avoid housing with very small ornamental crustaceans or newly settled invertebrates if these are a priority.

Special Requirements or Care Notes:
Best kept in a group of at least three, with five or more giving a more natural display where tank size allows. Provide plenty of shaded shelter and avoid aggressive or fast-feeding tank mates that may cause the group to hide. As with many cardinalfish, males may mouthbrood eggs, so settled groups may show breeding behaviour. A secure lid is recommended, as small startled marine fish can jump. Maintain stable water quality and feed appropriately sized foods.

Suitable for:
Beginner to intermediate fishkeepers

Availability:
Occasional in trade / Captive-bred where relevant

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Please note that Mother Nature is a wonderful thing, and variation in patterns and colours will occur — that is part of the unique beauty of these animals.