Silica Sand Filtration Media

Washed graded silica sand in 0.4-0.8 mm and 0.8-1.2 mm granulometries, packed in 25 kg bags. The media that does the actual filtering, from Waterstar Egypt.

The media does the filtering, the vessel only holds it

Inside every sand filter, the work is done not by the vessel but by the bed of graded silica it contains: water percolates down through the grains and suspended dirt lodges in the voids between them. Waterstar supplies this media in two granulometries, each packed in twenty-five kilogram bags: FM-4-8-25 with grains of 0.4 to 0.8 millimetres, the fine grade that forms the main capture layer, and FM-8-12-25 with grains of 0.8 to 1.2 millimetres, the coarser grade used where the specification calls for a bolder gradation. Proper filter sand is washed and graded — screened so the grain sizes stay within their stated band and rinsed free of dust and fines — because ungraded sand compacts, channels and bleeds cloudiness back into the pool.

Loading practice: how a filter is charged well

Loading a filter is simple work that rewards care. Fill the empty vessel roughly half way with water first, so the falling sand lands on a cushion instead of hammering the laterals at the bottom of the tank; many installers also cover the open standpipe so no grains drop inside it. Pour the bags in gradually, level the bed by hand, and complete the charge to the level the filter is designed for. After loading, run the first cycle on backwash and rinse rather than filter, so the residual dust goes to waste instead of into the pool. A top-mount vessel from the T-series or a side-mount vessel from the WS-series charged this way starts its service life with clear water from the first day.

When to replace the media

Silica does not wear out quickly, but it does not last forever. Over years of service the grains round off, the voids clog with oils and mineral scale, and the bed starts to channel: water finds preferential paths and passes through without being filtered. The practical signals are familiar — backwash cycles that come closer and closer together, pressure that stays high after backwashing, and water that never quite recovers its old clarity. As a working rule the bed is renewed every five to seven years, sooner in heavily loaded commercial filters such as side-mount batteries, later in lightly used residential ones. Send the filter model and its service history to the Waterstar factory engineers and they will specify the grades and the number of bags for a full recharge.