Description
Reef Rundown – Ring Cowrie (Monetaria annulus)
Why They're Cool: When active, the cowrie extends a living mantle over its shell, giving it a glossy, almost polished appearance. This mantle can fully cover the shell and retract quickly if the animal is disturbed.
Where You'll See Them: Most often grazing across rockwork and aquarium glass. They may also travel across sand surfaces, particularly at night.
Diet: Feeds primarily on film algae, diatoms, and biofilm growing on rock and glass. While grazing, they may also consume small amounts of detritus or leftover food.
Macroalgae Safe: Yes. Ring Cowries graze microalgae films and do not consume macroalgae.
Primary Use: Controlling film algae and biofilm on rockwork and aquarium glass.
Ease of Care: Easy. Like most cowries, they are capable of righting themselves if flipped.
Native Range: Indo-Pacific reef systems.
