Sand filters are important for cleaning water, and choosing the right filter media can make them work better. In a lab test, changing the sand size in the filter increased its efficiency by up to 5 times. Adjusting the backwash rate was needed when the media was changed. Using different types of media together can improve the filter's performance and make it easier to clean. Matching the properties of the different media layers is key for a well-functioning filter. The study showed that having the right mix of media types can make a big difference in how well the filter works and how often it needs to be cleaned.