Everyone wants a crystal clear pool and while sanitizing goes a long way towards keeping the water clean and healthy, there is another half to the equation: filtering. But it's not just a simple matter of installing the equipment. The type of media chosen for the filter can make a huge difference to the quality of the water and the amount of maintenance required. Sand and glass pearls are among the main options of filter media available on the market. Both have benefits and drawbacks to be considered.