Scientific name - Eucidaris tribuloides Family – Cidaridae Common name – Pencil, Mine, Club Urchin Max Size – 5 in (12 cm) Range: Caribbean, Philippines Care Level – Moderate Temperament – Peaceful Foods and feeding – It will roam the aquarium eating algae and other invertebrates Aquarium suitability - Reef compatibility – No Captive care – This urchin will hide during the day and come out at night to forage for algae and small invertebrates. It can damage corals. It should be in an aquarium with lots of hiding places and secured rockwork. It is known from moving rocks around. Also, if it holes up, never try and remove it. Its spikes will break before it will let go. Like all invertebrates it is extremely sensitive to nitrates and copper, and small amount are fatal to it.