The Pincushion Urchin boasts a body that can be oval to round in shape and is adorned with hundreds of spines that are uniform in size. Its color can vary and range from red, purple, white, to blue. When it comes to its habitat, the Pincushion Urchin requires ample hiding places and enough space to forage in a home aquarium. During the day, it typically seeks refuge in caves, and sometimes it even creates burrows in thick substrates. At night, it emerges to feed on algae, using its suctorial podia that are arranged in five doubled rows to move about. To ensure its proper nutrition, the aquarium should contain an abundant amount of live rock for it to graze on. However, it should be noted that the Pincushion Urchin may also feed on some of the sessile invertebrates in the reef system. Therefore, it’s important that the rock formations are stable and can withstand the movement of the Urchin as it wedges itself in crevices. The Pincushion Urchin is generally solitary but can tolerate others of its kind. It is sensitive to high levels of copper-based medications and will not tolerate high nitrates. Poor water quality can cause it to lose its spines.