purfiltrum is a unique macro-porous synthetic polymer that removes soluble and insoluble organic impurities from water 5 to 10 times faster and more completely than all other competing products.It is the highest capacity organic filtration resin on the market outperforming even SeachemPurigen, binding 10 to 15% more organic material.purfiltrum controls ammonia, nitrites and nitrates by removing nitrogenous organic waste that would otherwise be converted into these harmful chemicals. purfiltrum will not reduce the levels of trace elements, and it significantly raises redox. It polishes water to unparalleled clarity. purfiltrum progressively darkens as it removes impurities, and is easily renewed by treating with bleach per recommended regeneration instructions. purfiltrum is designed for both marine and freshwater use.