Yellowhead jawfish (Opistognathus aurifrons) care guide

Group
Marine fish
Family
Opistognathidae (jawfishes)
Origin
Caribbean coral reefs and Florida, in rubble and sand areas at 3–40 m.
Water
saltwater
Maximum size
10 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
Salinity SG 1.023–1.026
Minimum tank
115 litres
Care level
beginner
Temperament
peaceful
Reef safe
yes

Care

Jawfish dig burrows, so provide a deep bed of mixed sand and rubble (shell fragments and small pebbles) and keep a tight-fitting lid: they jump, especially when frightened. The list suggests about 115 litres (30 US gallons) with 13–18 cm of soft substrate. Water figures given here are general marine aquarium guidance, not species-specific: 24–27 °C, pH 8.1–8.4 and salinity SG 1.023–1.026, with stable, well-oxygenated water. In the wild it lives in groups of up to 70, usually showing just its head and front half out of the burrow. It moves sand, shells and stones in its mouth, blocks the burrow entrance with a stone when threatened and gapes at nearby fish to warn them off. One of the most tolerant jawfish towards its own kind: a small group can be kept at about one fish per 38 litres (10 US gallons) of tank. Sources: Wikipedia, List of marine aquarium fish species (en.wikipedia.org/wiki/Listofmarineaquariumfishspecies); Wikipedia (en.wikipedia.org/wiki/Opistognathusaurifrons). Checked October 2026.

Diet

Eats plankton. In aquaria it takes brine shrimp, mysis and frozen and pelleted foods; feed two or three times a day.

Breeding

A mouthbrooder: the male carries the eggs in his mouth until they hatch.

Compatibility and tank mates

Reef safe and peaceful. Avoid predators and aggressive fish such as large dottybacks. Make sure rockwork sits on the tank floor, not on sand it could undermine.

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

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