Diamond Goby Fish

The Diamond Watchman Goby, *Valenciennea puellaris*, is a popular and beneficial addition to the home aquarium. This active and industrious goby is known for its constant sifting of the sandbed, which helps to keep the substrate clean and aerated. Its body is typically a pale white or tan with numerous small, iridescent blue spots that shimmer in the light, giving it a “diamond” appearance. The head is often adorned with a few larger blue spots or lines.

A minimum tank size of 30 gallons is recommended for a single Diamond Watchman Goby, with larger tanks preferred for pairs or if housing with other bottom-dwelling species. A deep sandbed (at least 2-3 inches) is essential as this species is a prolific burrower and will create elaborate tunnels and burrows for shelter. Provide plenty of live rock and open sandbed areas for them to forage and build their homes. They are generally peaceful and can be housed with a variety of reef-safe fish and invertebrates. However, they may become territorial towards other sand-sifting gobies or similar-shaped bottom dwellers.

In the aquarium, the Diamond Watchman Goby primarily feeds on small invertebrates and detritus found within the sandbed. While they will actively sift for food, it is important to supplement their diet with a variety of frozen and live foods such as mysis shrimp, brine shrimp, and enriched flake or pellet foods. Target feeding near their burrow can be helpful to ensure they receive adequate nutrition, especially in tanks with a large number of competitors.

Diamond Watchman Gobies typically reach a size of about 6 inches in the home aquarium. They are considered reef-safe and will not harm corals or most invertebrates. While breeding in captivity is possible, it is not commonly achieved in the home aquarium setting. There are no readily apparent visual differences between males and females.