No homeowner or hotel guest wants to look at murky pool water, let alone swim in it.Cloudy water, however, can be an even more disturbing sight to service tech because when the water isn't clear, it means something's wrong with the pool. That something could include the filter medium. It's the medium's job to remove even the smallest particles of dirt from the water that passes through the filter And some media may do this better than others, depending on the pool, how it's used and how it's serviced. Professional service techs rely on a variety of chemicals and equipment to keep customers' pool water crystal clear--- and none, perhaps is more important than the pool filter: Without it, techs probably would lose the battle against dirt and debris. Now to expand the available arsenal of weapons, manufacturers have introduced new filter media that can be used in place of DE and sand.

Like diatomaceous earth (the most commonly used medium for precoat pool filters, perlite derives from a natural resource that has taken centuries to create a siliceous volcanic rock similar in nature to quartz and opal. Milled perlite has long been used as a fìltering aid and anti-caking agent in the pharmaceutical distilling and food-processing industries. But not until the past 10 years or so has the material been put to use in the pool industry. How did this material make its way from volcanoes to pool filters? Why can it improve your filter's performance? And perhaps most importantly, what effect does the use of perlite have on your pool maintenance routine?