{"product_id":"long-spine-black-urchins-medium","title":"Black Longspine Urchin (Diadema sp.)","description":"\u003cdiv style=\"font-family:Georgia,serif;line-height:1.65;\"\u003e\n\u003cdiv style=\"background:#FBE9E7;border-left:4px solid #D84315;padding:10px 14px;margin:0 0 14px;font-size:0.95em;\"\u003e\n\u003cstrong\u003eIn-store pickup only.\u003c\/strong\u003e Your order is reserved, we hold off on bagging until you arrive so it stays healthy in its display tank.\u003c\/div\u003e\n\u003cp\u003eThe \u003cstrong\u003eBlack Longspine Urchin (\u003cem\u003eDiadema\u003c\/em\u003e sp.)\u003c\/strong\u003e brings a striking silhouette and steady grazing activity to an established saltwater aquarium. Its slender black spines extend well beyond its small body, so open space matters as much as water volume. Sold individually, one urchin per order quantity.\u003c\/p\u003e\n\u003ch2 style=\"color:#D84315;\"\u003eCare at a glance\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eEnvironment:\u003c\/strong\u003e Established saltwater aquarium with mature live rock and room to graze.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiet:\u003c\/strong\u003e Algae grazer; supplement with plain dried marine seaweed as needed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTemperament:\u003c\/strong\u003e Peaceful, with very sharp defensive spines.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReef compatibility:\u003c\/strong\u003e Generally compatible, but grazing and movement can disturb loose frags and coralline algae.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWater:\u003c\/strong\u003e Stable marine conditions; avoid sudden changes in temperature or salinity.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIdentification:\u003c\/strong\u003e \u003cem\u003eDiadema\u003c\/em\u003e sp. Representative image shows \u003cem\u003eDiadema setosum\u003c\/em\u003e; species and appearance can vary by shipment.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 style=\"color:#D84315;\"\u003eA home with space to roam\u003c\/h2\u003e\n\u003cp\u003eArrange secure rockwork with sheltered resting places and broad routes between rocks. Allow clearance for the full spine span when planning the aquascape. A small purchase size does not mean a small adult footprint. Keep coral frags firmly mounted and leave delicate specimens out of narrow travel paths.\u003c\/p\u003e\n\u003cp\u003eLongspine urchins often shelter during bright periods and become more active as the lights dim. Observe its grip and grazing regularly. Acclimate carefully to the aquarium's salinity and temperature, and avoid copper medications in its system.\u003c\/p\u003e\n\u003ch2 style=\"color:#D84315;\"\u003eFeeding and compatibility\u003c\/h2\u003e\n\u003cp\u003eNatural algae should provide ongoing grazing opportunities. Once the rocks look clean, offer small portions of \u003ca href=\"\/products\/brs-nori-seaweed-sheets-20g\"\u003eBRS Nori Seaweed Sheets\u003c\/a\u003e within reach and remove uneaten pieces. Watch whether the urchin actually eats; a clean aquarium may not provide enough food for a large grazer.\u003c\/p\u003e\n\u003cp\u003eChoose tankmates that will leave the urchin alone. Do not assume its spines make it safe with animals known to eat or pick at invertebrates. Plan maintenance around its location, and never grasp it with bare hands. Its fragile spines can puncture skin and break.\u003c\/p\u003e\n\u003ch2 style=\"color:#D84315;\"\u003eExplore other grazers\u003c\/h2\u003e\n\u003cp\u003eCompare the more compact \u003ca href=\"\/products\/blue-tuxedo-urchin-mespilia-globulus-saltwater\"\u003eBlue Tuxedo Urchin\u003c\/a\u003e and \u003ca href=\"\/products\/pincushion-urchin-lytechinus-variegatus-saltwater\"\u003ePincushion Urchin\u003c\/a\u003e, or browse our \u003ca href=\"\/collections\/freshwater-invertebrates\"\u003eInvertebrates\u003c\/a\u003e. Choose a cleanup crew to fit the available food and space.\u003c\/p\u003e\n\u003ch2 style=\"color:#D84315;\"\u003eFrequently asked questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eHow many do I receive?\u003c\/strong\u003e\u003cbr\u003eOne urchin. Each quantity selected represents one animal.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill it live on algae alone?\u003c\/strong\u003e\u003cbr\u003eOnly when the aquarium supplies enough suitable algae. Check feeding and supplement with marine seaweed when grazing becomes scarce.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I pick it up by its spines?\u003c\/strong\u003e\u003cbr\u003eNo. Ask us about safe transfer and placement at pickup, and avoid handling the spines.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs every black longspine the same species?\u003c\/strong\u003e\u003cbr\u003eNo. Several \u003cem\u003eDiadema\u003c\/em\u003e species share this common name. Ask us to confirm the current animal's identity and size before choosing it for your aquarium.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Squeaky's Aquatics","offers":[{"title":"Default Title","offer_id":48071627309275,"sku":"SQ-BLACKLONGSPINE","price":39.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0767\/5209\/3403\/files\/6ac6dc9998f1614bf4c1e9f8_8b454cdb-f114-4c59-9f50-9b5d8e1d74c4_0_hq_P1Xa3.png?v=1791417644","url":"https:\/\/squeakysaquatics.com\/products\/long-spine-black-urchins-medium","provider":"Squeaky's Aquatics","version":"1.0","type":"link"}