Filter-lite is a light. Highly porous. Aggregate filter media. Its hardness (6.0 on Mohs Scale) makes this an excellent media for long term applications where frequent backwashing is required. This media has a wide dispersion of particle shapes which enables it to provide superb filtration and low pressure drops. Filter-lite is an inert media and is less than 3% acid soluble. Filtration in the 20 micron range is common.