Diamond Goby

The Diamond Goby, Valenciennea puellaris, is a highly active sand-sifting goby valued for both its attractive appearance and fascinating natural behavior. Its pale white to silvery body is decorated with rows of orange spots and dashes, while subtle blue markings around the face add additional color. Often called the Diamond Watchman Goby or Orange Spotted Diamond Goby, this saltwater fish spends much of its day taking mouthfuls of sand, filtering out edible organisms, and releasing the cleaned substrate through its gills.

Native to the Indo-Pacific from the Red Sea eastward to Samoa, extending north to southern Japan and south to the Great Barrier Reef and New Caledonia, Valenciennea puellaris inhabits sandy areas of lagoons and seaward reefs. Adults commonly live in pairs and use shallow burrows beneath rubble or rock as shelter.

The Diamond Goby is peaceful, reef safe, and especially appealing in established marine aquariums with substantial open sand beds. Its constant sand-sifting activity can help keep the upper substrate aerated and visually clean, but this behavior also means the species requires adequate feeding and should not be expected to survive solely on organisms found within the sand.

Quick Care Guide

Care Level: Moderate
Minimum Tank Size: 50 gallons
Temperament: Peaceful
Diet: Carnivore / Sand-Sifting Microfauna Feeder
Reef Safe: Yes
Region: Indo-Pacific – Red Sea to Samoa
Scientific Name: Valenciennea puellaris

Tank Requirements

Provide a mature saltwater aquarium with a substantial area of fine sand that can be continuously sifted without injuring the goby's mouth or gills. Fine aragonite sand is preferable to coarse, sharp, or highly abrasive substrate.

Rockwork should include caves, overhangs, and secure areas where the goby can establish a burrow. Because this species may excavate underneath rocks, major rock structures should rest securely on the aquarium bottom or otherwise be stabilized rather than relying entirely on loose sand for support.

Leave plenty of exposed sand around the aquascape for natural foraging. Mature live rock and an established sand bed also provide populations of small crustaceans and other organisms that supplement prepared foods.

A tightly fitted lid or fine-mesh aquarium cover is essential. Diamond Gobies are well known for jumping, particularly during introduction, after being startled, or when adjusting to unfamiliar surroundings.

Diet and Feeding

The Diamond Goby is a carnivorous sand sifter that naturally consumes small benthic crustaceans, worms, and other tiny organisms extracted while processing mouthfuls of substrate.

In captivity, offer frozen mysis shrimp, enriched brine shrimp, finely chopped marine seafood, copepods, small crustacean-based frozen foods, and quality sinking carnivore pellets or granules. Foods should be appropriately sized and allowed to reach the lower portion of the aquarium where the goby naturally feeds.

Feed at least two to three small meals daily when practical. Although a mature sand bed provides valuable natural forage, the aquarium's microfauna population alone may not supply enough nutrition indefinitely.

Monitor body condition carefully. A visibly hollow or pinched abdomen can indicate insufficient food intake, even when the fish appears to be actively sifting sand throughout the day.

Temperament and Tankmates

The Diamond Goby is peaceful toward most community marine fish and is generally an excellent choice for appropriately stocked reef and fish-only aquariums.

Territorial behavior is primarily directed toward other sand-sifting gobies or members of its own species. In nature, adults commonly occur as bonded pairs, and a confirmed compatible pair can often be maintained together. Unpaired individuals of the same species may fight, particularly when aquarium space is limited.

Suitable tankmates include clownfish, cardinalfish, peaceful wrasses, dwarf angelfish, blennies, and other community marine species that will not aggressively compete for bottom-dwelling foods.

Avoid highly aggressive or predatory fish that may intimidate the goby and prevent it from feeding normally.

Reef Compatibility

The Diamond Goby is reef safe and does not normally consume healthy corals, clams, or established ornamental shrimp, crabs, and snails.

Its sand-sifting behavior can, however, create practical issues in a reef aquarium. Sand may be deposited onto corals positioned close to the substrate, particularly plate corals, zoanthids, and low-mounted frags. Sensitive corals should be positioned high enough that repeated sand deposition does not become a problem.

The goby may also rearrange loose rubble around its burrow, so unsecured frags and small decorations should be stabilized.

Water Parameters

Temperature: 75–80°F
Specific Gravity: 1.024–1.026
pH: 8.1–8.4
Alkalinity: 8–12 dKH

Stable water quality is more important than continually adjusting parameters to reach exact numbers. Maintain consistent salinity, temperature, and pH, and avoid sudden fluctuations during acclimation.

Common Considerations

• Adults can approach 6–8 inches, so adequate bottom area and long-term swimming space are important.

• A mature aquarium with a substantial fine sand bed is strongly recommended for natural feeding and burrowing behavior.

• Do not rely on sand-sifting alone to provide adequate nutrition; frequent supplemental feeding is important.

• This species is an accomplished jumper and requires a securely covered aquarium.

• Sand may be deposited on low-growing corals and frags, so coral placement should account for its constant substrate-sifting behavior.