Golden trevally (Gnathanodon speciosus) care guide

Group
Marine fish
Other names
Golden kingfish, Banded trevally, King trevally, Ulua pa'opa'o
Family
Carangidae (jacks and trevallies)
Origin
Tropical and subtropical Indian and Pacific Oceans, South Africa to Central America, Japan to Australia and New Zealand; inshore reefs and sand.
Water
saltwater
Maximum size
120 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.020–1.025
Care level
intermediate
Temperament
semi_aggressive
Reef safe
no

Care

The list gives no maximum size; the species article gives 120 cm and 15 kg, so we use that. Juveniles are sold for their yellow and black bars, but this fish is for public-aquarium-sized systems: it outgrows home aquaria and needs a very large volume of open swimming space, so no home tank size is given. Water figures given here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and salinity SG 1.020–1.025 (fish-only systems). Juveniles school and follow larger animals such as groupers, sharks and jellyfish; adults are mostly solitary or in small groups. Aquaculture for the aquarium trade has been achieved in Singapore. Selling: our policies require the adult size and long-term tank needs to be stated clearly in the listing. Large fish must travel by a specialist live-animal courier (see the Livestock shipping guide). Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Gnathanodonspeciosus). Checked October 2026.

Diet

A daytime predator that sucks crustaceans, molluscs and small fish from sand and reef. Feed chopped fish, prawn, squid, krill and large pellets.

Breeding

Not bred in home aquaria. In Hawaii it spawns from February to October, in the evening and at night; laboratory culture has been achieved.

Compatibility and tank mates

Not reef safe: it eats crustaceans, molluscs and small fish. Keep in schools with other large, robust fish.

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

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