Pearly Jawfish (Opisthognathus aurifrons)

The Pearly Jawfish (Opisthognathus aurifrons) is a fascinating Caribbean reef fish with a pale, iridescent body and a sunny yellow head. These charismatic burrowers spend their days hovering vertically above hand-dug tunnels, retreating into them at the slightest disturbance. Intermediate-care, peaceful, and reef-safe — they reward the right setup with months of constant, almost-cartoonish activity.

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Care Guide

• Tank size: 30 gallons minimum, longer footprint preferred over height.
• Substrate: Critical — they need a deep (4"+) mixed substrate of fine sand and crushed coral or rubble so they can excavate stable burrows. Add small rocks and shells on top; they will use these to "build a door" each night.
• Lid: Tight-fitting lid is non-negotiable. Pearly Jawfish are accomplished jumpers, especially when startled or housed with aggressive tankmates.
• Water parameters: 72–78°F, salinity 1.020–1.026, pH 8.1–8.4.
• Diet: Carnivore. Feed 2–3 small meals daily of live copepods, frozen mysis, enriched brine shrimp, and finely chopped meaty foods.
• Reef safe: Yes — fully reef and invert safe.

Specifications

Compatibility

Pearly Jawfish are model peaceful community reef citizens — but their nervous, burrowing nature means tankmate choice matters. Stick with calm, similarly-sized fish.

• Good tankmates: Clownfish, peaceful gobies, blennies, cardinals, chromis, small wrasses.
• Avoid: Aggressive damsels, dottybacks, large angels, predatory fish, or anything that will outcompete them at feeding time.
• Numbers: Best kept singly unless in a very large tank (75g+) with plenty of substrate real estate.

Recommended Foods & Supplies

• Nutramar Tigrio Live Copepods — perfect target food for new arrivals.
• Bulldawg Copepod Mix — multi-species live pods.
• SFBB Freeze-Dried Mysis Shrimp — staple frozen-style food.
• Bulldawg Artemia Brine Shrimp — gut-loaded live brine.
• Full saltwater nutrition collection.

FAQ

Why do they need such deep substrate?
Pearly Jawfish dig their own vertical burrows and reinforce the walls with shells and rubble. Less than 3–4 inches of substrate and they can't establish a proper home, which causes chronic stress.

Will they really jump out?
Yes — Pearly Jawfish are one of the most notorious jumpers in the saltwater hobby. A tight-fitting lid or fine mesh screen is required.

Are they reef safe?
Completely. They won't touch corals, anemones, or inverts. They may shift rubble around their burrow entrance, so don't place loose frags right above their tunnel.

What size will I receive?
Approximately 2.5–3.5 inches. Sizes vary with each shipment.