Scaly lizardfish

Where they come from

Scaly lizardfish turn up across the Indo-West Pacific on sandy and silty bottoms along reefs and coastal shelves. Picture a twilight sand flat with a scattered rubble line, light current, and lots of places to lie in wait. They are classic ambush predators that spend most of the day parked on the bottom, then perk up at dusk.

Setting up their tank

These are not community display fish. Think species tank, big footprint, quiet flow, and a clean, oxygen-rich system. Mine settled in a 6-foot tank with a wide sand flat and just a few low ledges.

• Tank size: 180 gal+ for a single adult (they reach 30-40 cm). Go longer over taller.
• Substrate: 2-3 inches of fine sand. They like to hunker down and sometimes half-bury.
• Aquascape: Low rockwork or stable rubble lines with open lanes for strikes. Add a couple of snug caves or PVC sections partly buried for security.
• Flow: Moderate laminar flow across the sand. Avoid blasting the bottom.
• Lighting: Dim to moderate. They are crepuscular and do better without harsh lighting.
• Lid: Tight-fitting, every gap covered. They launch like torpedoes when spooked.
• Filtration: Big skimmer and ample biofiltration. Carnivore waste loads add up fast.
• Water: 24-26 C, 1.025-1.026 sg, pH 8.0-8.3, dKH 8-10, nitrate under 30 ppm with regular water changes.

Acclimate slowly with lights off. I drip for 45-60 minutes, then leave the room for a bit so it can settle without faces pressed to the glass.

What to feed them

They are sight-driven predators. Movement helps. Most new arrivals ignore pellets and flakes, but you can wean them onto frozen with a little patience.

• Starter foods: live ghost shrimp or small saltwater fish to trigger the hunt response.
• Transition: frozen silversides, lancefish, squid strips, raw shrimp, and marine fish chunks offered on tongs with a bit of wiggle.
• Routine: 2-3 good meals per week for adults; smaller daily snacks for juveniles. Avoid stuffing them daily to prevent fatty deposits.
• Supplements: Soak foods in a vitamin/omega prep a couple times a week to cover gaps.
• Avoid: feeder goldfish/rosies (thiaminase, poor nutrition) and oily freshwater fish.

How they behave and who they get along with

Think solitary ambush hunter. They spend a lot of time motionless, then explode into action. Mine learned the feeding routine and would creep closer as lights dimmed.

• With their own kind: best kept singly. Conspecifics usually end in stress or a mauling unless the system is huge with multiple territories.
• With other fish: anything bite-sized will disappear. Even fish half their length can be fair game if shaped like prey.
• Possible tankmates (with caution): large, robust fish that stay higher in the water column and do not harass the bottom, e.g., big tangs or rabbitfish. Expect some risk.
• Poor choices: gobies, blennies, wrasses, anthias, cardinals, small triggers, crustaceans, and ornamental shrimp. Rays and small sharks compete for bottom space and can cause stress.

Breeding tips

Realistically, not a home-aquarium project. They broadcast spawn and the eggs/larvae are pelagic. Sexing adults is not straightforward, and courtship needs space and cues we do not reliably provide. I have not seen or heard of a confirmed home spawn for this species.

Common problems to watch for

• Refusal to eat: very common at first. Try live ghost shrimp at dusk, reduce light, and add gentle flow across the feeding zone. Once it takes live, start mixing in frozen.
• Mouth and jaw injuries: they hit glass or rock during a missed strike. Keep the front pane clean and avoid sharp rock edges near the hunting lane.
• Internal parasites: wild-caught fish often carry worms. After it is eating, run praziquantel in QT and observe feces/appetite.
• Bacterial infections on abrasions: they rest on sand and can scrape themselves. Keep sand clean and water quality high; treat promptly in QT if you see redness or fuzz.
• Jumping: startled launches crack lids and dry fish. Use tight covers and keep the room calm during lights-on/off.
• Stress from bright light and traffic: use a gradual ramp on your lights and give them shadowed areas to park.