Bio-Chem Stars are a biological filtration medium that provides a substrate for the optimal growth of beneficial bacteria which break down organic wastes in an aquarium. Their internal pore structure is formed under a patented process that creates a 50-70 micron internal pore network. This pore size is optimal for the growth of beneficial bacteria, including nitrifying bacteria that remove toxic ammonia and nitrite. It also allows the best oxygen and water transfer through the star, which keeps bacterial colonies healthy and active.
Because of this complete internal colonization, Bio-Chem Stars are the most efficient biological filter medium available for use in FilStar Canister Power Filters. Periodic replacement of half the stars is recommended for best results.