Purple Short Spine Urchin (Echinometra sp.)
Purple Short Spine Urchin (Echinometra sp.)
Echinometra’s claim to fame is architectural: it grinds a shelter pit directly into reef rock using its own spines and test, wearing the same burrow down over years until the urchin is essentially potted in solid stone. Those spines are short, thick, and deep purple rather than the long needle spines of a pincushion or longspine urchin, which makes it a lower-risk urchin to reach past during tank maintenance. It grazes algae from rock and glass steadily, day or night, and rarely bothers anything else in the tank.
Care level: Easy · Temperament: Peaceful · Max size: ~2" body · Min tank: 20 gal · Reef safe: With caution (may knock over frags) · Diet: Herbivore, algae
At a glance
- Scientific name
- Echinometra sp.
- Common name
- Purple Short Spine Urchin
- Water type
- Saltwater
- Care level
- Easy
- Temperament
- Peaceful
- Max size
- ~2" body
- Minimum tank
- 20 gal
- Diet
- Herbivore, algae
- Reef safe
- With caution (may knock over frags)
When it ships
Most non-quarantined stock goes out the week you order. If we do not already have the animal in-house we source it first — allow up to two weeks for it to reach us. Live animals leave Monday and Tuesday, and Early AM Overnight is the only service that carries a live arrival guarantee.
The live guarantee
Shipped Early AM Overnight: a 1-hour DOA window from confirmed delivery, and nothing beyond it. Next Day Air and 2-Day carry no live arrival guarantee, and neither does USPS Priority. Local pickup or local delivery: 24 hours, if you bring a water sample from your aquarium and we test it before the animal goes home. Maintenance clients: 60 days when we service the aquarium at least twice a month, 28 days on a monthly plan.
Expert guidance
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