Choosing a Sea Urchin

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Sea urchins are an interesting and challenging addition to the saltwater reef aquarium. These invertebrates provide a unique and distinctive appearance that lends to a more natural looking reef tankEclipse Curved-Front Aquarium System
Marineland/Aquaria Eclipse Aquarium System has unique combinations of beauty, precision and 3-stage BIO- Wheel filtration efficiency, the Eclipse Aqua.... Urchins may be kept successfully with many saltwater fish or as part of a liveJumboKrill Freeze Dried Jumbo Shrimp
These whole, freeze-dried shrimp are an excellent source of protein, fat, vitamin E and roughage for all large, carnivorous tropical and marine fish. ... rock40lb Look Alive Reef Rock
Why wait? CaribSea 40lb Look Alive Reef Rock are already in living color! We begin with actual pieces of real coral rock, then add pink and green cora... and coral display.

Appearance and Behavior

Sea urchins are easily recognized by their long pointed spines radiating from a round or sometimes flattened center. Their mouths are not visible, being located on the underside of the body. Urchins move slowly by the use of small rows of feet and the waving action of their spines. They will scavenge the tank looking for small bits of food, algaeMarine Algaefix
Marine Algaefix is EPA-registered as reef-safe. Algaefix® Marine controls many types of algae in marine & reef aquariums. It will not harm marine fish... or other tank debris. Do not expect a lot of animation from sea urchins. The main appeal is their graceful beauty. The urchin has spines that can reach 3 to 6 inches in length.

Feeding and TankEclipse Curved-Front Aquarium System
Marineland/Aquaria Eclipse Aquarium System has unique combinations of beauty, precision and 3-stage BIO- Wheel filtration efficiency, the Eclipse Aqua... Requirements

Sea urchins make their living as scavengers but sometimes will actively hunt small prey. This should not be a great concern for the average saltwater tank. They will move slowly about the rocks and gravel. They may eat tablet foods designed for bottom feedersSinking Wafers
Hikari Sinking Wafers is a Scientific Diet For Catfish, Loaches & Other Bottom Feeders providing them. Exacting Nutrition Hikari Tropical Sinking ..., small pieces of fish fillet or vegetable foods. They should not be relied upon to keep a tank clean of uneaten food or fish waste, however; regular tank maintenance still applies. Most urchins do well in average marine aquarium conditions. Maintain temperature between 74 to 78 degrees Fahrenheit and specific gravity between 1.020-1.023. Expect a life span of 6 months to 3 years depending on tank conditions and successful feeding.

Special Concerns

Use extreme caution in handling sea urchins. Those beautiful spines are poisonous. If you've ever stepped on a sea urchin while visiting the beach you know they can inflict a painful sting. Some fish use the spines to hide in for protection from predators. Cardinal fish and triggerfish eat urchins as part of their natural diet so don't mix these species together in the same tank.