Filter sand cleaning Overview It was thought that over time filter sand became rounded and the filters became contaminated with body fats. This would reduce filter efficiency and water clarity. High combined chlorine with the associated odours will also be a symptom of poor filtration. It was therefore recommended that filter sand should be changed or skimmed at least every year. **This is no longer the case**. Filter sand does not wear out, silica sand is extraordinarily hard and will withstand years of agitation in a pool filter vessel. The sand can now be cleaned effectively and economically using Topline's cleaning system with our own chemical formula "SILICA WASH". Topline took examples of filter sand 10 years old and this sand, after cleaning, was placed under a digital microscope and compared with new sand. New sand Cleaned sand It can be seen from the comparison of the two samples that there is no visible rounding of the sand. This test was repeated on several samples from different filters with similar results. It can therefore be concluded that sand does not age. This being the case, sand does not need changing, just cleaning. Cleaning process To clean the sand, the filter is isolated from the filtration system. The lid can then be removed and the filter filled with water. The "Silica wash" is then added to the filter and the filter sand agitated using a high capacity pressure pump. During the agitation process the body fats are lifted from the sand, this can be clearly seen on the picture below. The filter lid is then re-attached, the filter backwashed and rinsed and the filter put back into service. The waste material is no different from a concentrated backwash. Filters treated in this way are put back into service having had the majority of the body fats removed and should not need treating any more frequently than the normally recommended sand change frequency. In addition, not only is the sand cleaned but the filter vessel itself is degreased. This is something that a simple sand change will not do. COSTS When compared with the cost of replacing sand the Topline system is typically 50% cheaper and will provide a quick and efficient method to meet a companies obligations to the users of swimming pools and spa's. Tel: 01323 440760 or E-mail: info@topline.uk.net for information sales@topline.uk.net Sales enquiries Topline Electronics Limited Unit A8 Ropemaker park Diplocks Way Industrial Estate Hailsham, East Sussex, BN27 3GU In order to maintain the highest standards, Topline reserves the right to alter specifications without notice.