Scientific name - Cladophora Aegagropila Common terms - Moss Ball, Marimo, Cladophora Ball, torasanpe, Lake ball Geographic origin - Certain lakes in Japan, Iceland, Estonia Type (stem, bulb, rhizome, floating etc.) - Free floating. Can be used as a carpet layer. Max. size (height, width) - Up to 30cm in diameter in the wild. Generally smaller in home aquaria. Lighting required - low to moderate - marimo will float due to pearling with higher light levels. Temperature - <25C Water chemistry requirements (pH, hardness) - Adaptable. Can tolerate some salinity. Growth rates - slow (about 5mm per year) Demands - undemanding Additional info - An excellent and attractive addition to any freshwater tank. Being a form of algae (not moss), it tends to hinder the growth of other algaes by outcompeting them for the same nutrients (note: it won't 'cure' an algae infested tank). Requires regular turning to help keep it's spherical shape. Tends to pick up detritus, so may need rinsing occasionally -- just remove it from your aquarium and give it a few squeezes in some tank water. You may notice a few stray filaments floating about the bottom of your tank. This is normal - they'll eventually grow into a carpet or a baby moss ball. Amano shrimp seem especially fond of these plants. Trivia - Marimo have been granted the status of "Special National Treasure" in Japan. In Iceland it's believed that taking good care of the plant will "make your wishes come true".