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The Blue Tuxedo Urchin, also known as the Sphere Urchin or Globe Urchin, has five to ten broad-colored bands usually blue or black, with red, brown, or dark spines. This very striking combination, gives it the "formal" look and thus the name "Tuxedo Urchin."
During the day, it will hide among the rocks, in crevices, or under plants in a sandy substrate. At night, it will emerge to graze on the algae present in or near its home. The Tuxedo Pincushion Urchin generally roams alone, but several of them could be housed in the same aquarium if it is large enough to provide them with adequate food (algae) and shelter. It is sensitive to high levels of copper-based medications and it will not tolerate high nitrate levels. If it starts to lose a number of spines, it is often due to poor water conditions.
If algae levels are particularly low, its diet will need to be supplemented with dried seaweed.