The ORA Sand Sifting Cucumber is a valued cleanupcrew addition sold instore here in Columbus, Ohio. It acts as a sandsifting starfish that aerates substrate, helping reduce maintenance and improve water quality. Stock 1 per 50 gal in a balanced reef or fishonly system for best results. Difficulty: Moderate. Needs large, established sand bed. Dripacclimate and maintain stable salinity for longterm health.