Just as the pump is the heart of the pool circulation system, the filters are its kidneys. As pool water is circulated, it is passed through a filter or bank of filters where dirt, hair, pollen, and other small particles are trapped and, when the filter media is cleaned, flushed out of the system. In most cases, pool water enters the top of the filter tank, travels downward through the filter medium, and exits as clean water at the bottom of the filter tank.

It is important to note that the filters do not remove bacteria, viruses, fungi, or algae. Killing bacteria and other harmful organisms is the job of the disinfection system. Although adequate turnovers are an important prerequisite for good water clarity, the type of filter medium has much to do with the effectiveness of the filter. Basically, there are three types of filter media: sand, diatomaceous earth (DE), and cartridge. Filters that produce the best water clarity may also require the most work. Before deciding on a particular filter, weigh the importance of superior water clarity against case of operation. Overall, the cost of these filters is similar, and they all should be cleaned weekly.

Water Chemistry • Popular Disinfectants • Chorine • Calcium Hypochorite • Sodium Hypochlorite • Stabilized Chlorines •
Bromine • Other Disinfectants • Water Balance • pH • Total Alkalinity • Calcium Hardness • Total Dissolved Solids •
Balancing Pool Water • Water Testing • Pool Vacs & Sweepers •

Pool Maintenance • Daily Chores • Weekly Chores • Solving Common Problems • Cloudy, Milky Water • Malodorous, Irritating Water
Green Water • Red or Brown Water • Blue - Green Water • Blue or Black Water • Pump Problems • Sand in Pool •
Excessive Water Loss • Excessive Foaming