Watchman Goby

Aquarium Requirements

• Minimum Tank Size: 40 gallons (150 litres)

• Temperature: 24–27°C (75–81°F)

• pH: 8.1–8.4

• Specific Gravity (Salinity): 1.020–1.025

• Alkalinity: 8–12 dKH

• Ammonia & Nitrite: 0 ppm

• Nitrate:< 10 ppm

• Aquascape: Provide a fine sandy substrate (3–5 inches) for burrowing and sifting, along with live rock for shelter and natural grazing surfaces

Watchman Gobies thrive in established aquariums with stable water parameters and a sandy substrate that allows for their natural digging and feeding behaviors.

Diet and Feeding

Watchman Gobies are carnivorous sand sifters and feed primarily on small invertebrates found in the substrate:

• Frozen or live foods such as mysis shrimp, brine shrimp, and finely chopped seafood

• High-quality sinking pellets or marine flakes formulated for carnivorous fish

• Feed 2–3 times daily, ensuring food reaches the substrate where they naturally forage

A varied diet supports strong coloration, vitality, and active behavior.

Temperament and Compatibility

Watchman Gobies are peaceful, bottom-dwelling fish that coexist well with other non-aggressive species. They may become territorial toward similar gobies if kept in smaller tanks but generally remain calm in larger aquariums.

Tankmate Recommendations:

• Suitable: Clownfish, blennies, firefish, small tangs, and other peaceful reef species

• Avoid: Large, aggressive, or predatory fish

Providing sand for burrowing and plenty of hiding spots encourages natural behavior and reduces stress.

Reef Compatibility

✅ Reef Safe

Watchman Gobies are reef safe and do not harm corals or sessile invertebrates. Their sand-sifting behavior also helps maintain a healthy, aerated substrate in reef aquariums.

Additional Information

• Maximum Size: Up to 15 cm (6 inches)

• Lifespan: 5–7 years with proper care

• Difficulty Level: Easy to Moderate

• Natural Behavior: Peaceful, sand-sifter, bottom-dweller, may burrow under rocks for shelter

• Origin: Indo-Pacific, including Indonesia, the Philippines, and the Great Barrier Reef

The Watchman Goby (Amblygobius phalaena) is a peaceful and practical addition to reef and community aquariums, offering both visual appeal and substrate maintenance. With stable water parameters, a sandy substrate, and a protein-rich diet, it thrives as a long-lived and engaging member of the marine aquarium community.