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Red Slate Pencil Urchin
(Heterocentrotus mammillatus)
Quick Care FactsCare Level: Easy
Temperament: Peaceful
Maximum Size: 8"
Diet: Omnivore
Aquarium Level: Substrate & Rocks
Minimum Tank Size: 30 gallons
Reef Compatible: No
Water Conditions: 72-78° F, dKH 8-12, sg 1.020-1.025, pH 8.1-8.4
Supplements: Calcium, Iodine, Strontium, Trace elements, Marnesium
Coloration: Red, Pink
Origin: Hawaiian Islands
Family: Echinometridae
Species: Urchins
Species Information
The Red Slate Pencil Urchin or simply the Slate Pencil Urchin, has a reddish-brown body and long, blunt, tapering solid spines. The spines radiate out from the body in all directions at lengths of up to five inches or so. The spines of the Red Slate Pencil Urchin are often described as looking like pencils and were used as writing utensils for slate boards, thus this species is also sometimes referred to as the Red Slate Pencil Urchin.
Overall this species is very easy to maintain within the marine aquarium environment and will also benefit the aquarium by grazing on algae on the glass and rocks.
Aquarium Care
Red Slate Pencil Urchins require a fair amount of room to move about the aquarium and a sturdy rock scape to support its size and scraping motion as it move along the reef. The Red Slate Pencil Urchin moves about via its suctorial podia, which provides enough traction to allow it to climb up the glass walls of an aquarium or to move over rocks and sand. Red Slate Pencil Urchins can be destructive and even harmful to corals, but is safe in a fish-only aquarium.
Red Slate Pencil Urchins are generally solitary, and in the aquarium environment it is generally best to keep just one of its kind per tank. Being nocturnal, it will usually be less visible during daylight hours and wait for the cover of night to forage for algae. The Red Slate Pencil Urchin prefers low nitrate levels and will not tolerate copper-based medications, if exposed to copper it is not unusual for it to lose a few spines.
If this species sheds many of its spines, it is often due to poor water quality. No specific water movement, lighting or other aquarium conditions are required to successfully house this species.
Feeding & Nutrition
The Red Slate Pencil Urchin will do well to have live rock, which will provide a good source for grazing. If there is insufficient algae on the rock or glass of the aquarium for the Red Slate Pencil Urchin to graze, the diet should be supplemented with dried seaweed or similar foods.
Additional Photos