Golden-striped soapfish (Grammistes sexlineatus) care guide

Group
Marine fish
Other names
Golden stripe soapfish, Lined soapfish, Sixline soapfish, Golden-striped bass, Six-lined perch, White-lined rock cod, Radio fish
Family
Serranidae (groupers and sea basses; soapfish group)
Origin
Indo-Pacific, from East Africa and the Red Sea to Hawaii, southern Japan and northern New Zealand; rocky and coral reefs to about 50 m.
Water
saltwater
Maximum size
30 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.020–1.025
Minimum tank
600 litres
Care level
intermediate
Temperament
semi_aggressive
Reef safe
no

Care

Tank and decor: a fish-only system with plenty of crevices and caves to hide in. The tank size given is an estimate based on its adult size. Water: the sources give no species-specific figures, so the values here are general marine aquarium guidance: 24–27 °C, pH 8.1–8.4 and specific gravity 1.020–1.025. Keep nitrate low and the water well oxygenated. Behaviour: usually solitary, hiding in crevices by day and most active at night. Toxin warning: when stressed the skin releases a soapy-looking mucus containing toxins called grammistins. In a closed tank this can harm or kill tankmates, so avoid stressing it, net it gently and do not ship it in the same bag as other fish. Wash your hands after handling it. Identification: dark brown with pale yellow to white lengthwise stripes. Very small juveniles are spotted; stripes appear as the fish grows (three at about 5 cm, six at about 8 cm) and may break up in large adults. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Grammistessexlineatus). Checked October 2026.

Diet

A predator of small fish and crustaceans. Offer meaty marine foods such as prawn, fish, squid and mysis; it learns to take frozen food readily.

Breeding

Not described in the sources, and not bred in home aquaria.

Compatibility and tank mates

Not reef safe: it eats small fish and crustaceans. Keep with fish too large to swallow. Its skin toxin can affect tankmates if it is stressed, so do not keep it with fish that will harass it.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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