Short Spine Urchin

Tripneustes gratilla

Identification	Round body with short white or dark spines and a surface covered in reddish-orange tube feet. Often collects and carries pieces of shell, rubble, and algae on its top surface for camouflage.
Maximum Length	5 inches
Origin	Indo-Pacific
Minimum Tank Size	50 gallons
Reef Compatibility	Reef safe

Behavior

Active algae grazer with fascinating camouflage behavior — will pick up and carry pieces of rubble, shell, and algae on its top surface, sometimes resembling a small moving pile of debris. Also known as the "collector urchin" or "hat urchin." Hardy and adaptable in established reef tanks.

Diet & Feeding

Herbivore. Grazes on macroalgae, turf algae, and cyanobacteria. Effective for nuisance algae control in larger systems.

Cautions

Can dislodge unsecured corals and frags as it moves. Handle carefully — short spines can still irritate skin. Provide adequate algae or supplement with nori.