Marimo Moss Ball (Chladophora aegagropila)
Commonly known as the Japanese Moss Ball or simply Marimo Ball. Shrimp, fish and many other aquatic species love to graze off these moss balls as they tend to collect debris, acting as natural filters.
Very easy to maintain and will slowly grow with moderate lighting.
Size is about 1 - 1.5" for small and 2 - 3" for large.