Engineer Goby (Pholidichthys leucotaenia)

The Engineer Goby (Pholidichthys leucotaenia) is one of the most entertaining oddballs in the saltwater hobby: an eel-shaped excavator that spends its life designing and maintaining a network of tunnels under your rockwork. Juveniles wear a crisp black and white racing stripe, and as they grow the stripe breaks apart into bold bands and spots, so the fish you take home keeps changing its outfit for the first year or two. Hardy, peaceful, and reef-safe, it is beginner friendly as long as you build the tank with its construction habit in mind. Browse the rest of our saltwater livestock and supplies to round out the crew.

Care Guide

• Tank size: 55 gallons or larger for an adult. They start small but grow into foot-long, eel-shaped adults that need floor space to tunnel.
• Aquascape rule number one: seat all rockwork directly on the tank bottom, never on top of the sand. An Engineer Goby will excavate under everything, and rocks resting on sand can shift or collapse.
• Substrate: a deep bed of sand mixed with rubble, 2 to 3 inches or more, gives it proper tunneling material.
• Water parameters: 72 to 78°F, pH 8.1 to 8.4, salinity 1.020 to 1.026. Very forgiving once the tank is stable.
• Feeding: carnivore. Offer meaty frozen foods like PE Mysis and brine shrimp, plus sinking pellets. Shy at first and most active around dusk, it becomes bolder at feeding time as it settles in.
• Lid: recommended, as with most elongated fish, especially while it learns the tank.

Specifications

Compatibility

Peaceful toward everything it cannot swallow whole, and big enough as an adult that almost nothing bothers it. Great tank mates include the Firefish Goby, Royal Gramma, Blue Green Chromis, Banggai Cardinal, and cleanup crew inverts like the Scarlet Skunk Cleaner Shrimp. Corals are safe, but mount frags on rockwork or racks rather than the sand, since the construction crew below can bury anything at ground level. If you love sand-dwelling personalities, our White Sleeper Goby and Diamond Sleeper Goby make great co-workers in larger tanks.

Recommended Foods & Supplies

• Piscine Energetics PE Mysis frozen food
• Xtreme Marine PeeWee Pellets slow-sinking staple
• Vitalis Marine Grazing Pellets

FAQ

Is it actually a goby?
No, and it is not a blenny either. The Engineer Goby is the only member of its own family, Pholidichthyidae. The common names stuck anyway.

Why does mine look different than the photo?
They transform as they grow. Juveniles have a clean horizontal stripe, and adults develop bold vertical bands and spots on an eel-like body. Watching the pattern change is half the fun.

Will it destroy my aquascape?
It will remodel the ground floor. With rockwork seated on the glass and corals mounted up on the rocks, the digging is harmless and honestly fascinating to watch.

I never see it. Is that normal?
Completely, especially the first few weeks. It works the night shift and peeks out at feeding time. Most become noticeably bolder once they associate you with food.