Common name: Collector Urchin

General Information

The Collector Urchin, scientifically known as Tripneustes gratilla, is a fascinating marine invertebrate popular among reef aquarium enthusiasts. Known for its unique behavior of adorning itself with bits of algae, shells, and other debris, this urchin is both a useful and decorative addition to marine tanks. Its common names, "Collector Urchin" and "Short-spined Sea Urchin," reflect its distinctive habit of collecting items and its relatively short spines compared to other urchin species.

In the aquarium trade, the Collector Urchin is valued not only for its aesthetic appeal but also for its role in algae control. It helps maintain a clean tank environment by grazing on various types of algae, making it a beneficial inhabitant for reef tanks. Moreover, its presence can contribute to the ecological balance within the aquarium setup.

Care

Caring for a Collector Urchin is relatively straightforward, making it suitable for aquarists of varying experience levels. It thrives in well-established aquariums with ample live rock, which provides both food and shelter. Maintaining stable water parameters is crucial for its health, as sudden changes can stress the urchin.

To mimic its natural habitat, provide a tank with plenty of live rock and a substrate that allows it to move freely. Ensure the tank has adequate calcium levels, as this is essential for the growth and maintenance of its spines and shell.

Diet and Feeding

The Collector Urchin is primarily a herbivore, feeding on a variety of algae. In captivity, it should be provided with a diet that includes natural algae growth on rocks, supplemented with dried seaweed or algae wafers if necessary. This helps ensure it receives adequate nutrition, especially in tanks where natural algae might be insufficient.

Behavior and Compatibility

Known for its peaceful nature, the Collector Urchin is a compatible addition to most reef tanks. It poses no threat to fish or corals, making it a reef-safe option. However, its tendency to "collect" items means it might occasionally rearrange small, loose objects in the tank.

While not aggressive, its spines can cause minor injuries if handled carelessly. It is best observed rather than handled frequently.

Health and Common Issues

With proper care, the Collector Urchin can thrive for several years in captivity. Key to its health is maintaining stable water conditions and providing a diet rich in algae. Regular monitoring of calcium and other trace elements in the water will support its skeletal health.

When selecting a Collector Urchin, look for individuals with intact spines and a healthy, active demeanor. Avoid urchins that appear damaged or are missing many spines, as this can indicate stress or poor health.

Habitat

Naturally found in warm, shallow waters throughout the Indo-Pacific region, the Collector Urchin inhabits coral reefs and seagrass beds. Its distribution includes areas such as the Red Sea, East Africa, the Indian Ocean, and the western Pacific Ocean, extending to Hawaii and other Pacific islands.

The Collector Urchin prefers environments with abundant algae growth, which provides both sustenance and camouflage. In captivity, replicating these conditions will help ensure its health and longevity.