Filter Enhance is a cellulose powder designed to significantly enhance filtration. It is applied by mixing with water and poured into the skimmer. It catches in the filter, coating the existing media allowing the removal of much finer particulate. It also acts as an absorbent, removing oils, greases and other forms of waste. The perfect product to use when removing dead algae, pollen, pollutants, oils and chelated metals. A very effective water polisher and clarifier.