• A pool filter ensures that pool water remains free of small plants, animals and debris.pool image by Pefkos from Fotolia.com
  
  A pool's filter ensures that the water in the pool is safe and clean for swimmers. Selecting and maintaining an appropriate filter for the needs of your pool is essential in guaranteeing that pool water remains free of small debris and bugs. There are several types of pool filters to choose from and each varies in the kind of installation and maintenance it requires. Trouble shooting tips for your pool filter will guide you through any performance problems that may arise.
  
  

Types of Filters

• All pool filters work in basically the same way. A small motor draws water into the filter, where it is drawn through some sort of filtering medium before being sent back into the main pool area. The three most common types of pool filters are sand filters, diatomaceous earth (DE) filters and cartridge filters.
  
  A sand filter pulls the pool water through very fine-grain sand; the sand collects small pieces of debris but allows the water to pass through. Sand filters are popular because they are inexpensive and increase in effectiveness over time. Sand filters need to be sanitized every two weeks.
  
  A DE filter uses a similar process except, instead of sand, the water is filtered through a fine powder made from crushed fossils of tiny animals. It is more efficient than a sand filter because it traps smaller particles, although it tends to be slightly more expensive.
  
  A cartridge pool filter pulls water through a series of paper or polyester filters. Filters are reusable and must be cleaned regularly. Although they are more expensive than sand filters, cartridge filters operate effectively at low water pressures and are ideal for energy-saving pool systems.
  
  

Cleaning Filters

• All pool filters must be cleaned regularly to maintain their effectiveness.
  
  Sand filters must be back washed each week to clean and rotate the sand. Back washing instructions accompany all pool pump systems. The sand in a sand filter must be completely replaced every two to five years, depending on the length of the swimming season.
  
  DE filters likewise require back washing. DE granules must be properly disposed of at a hazardous waste station. Some pool experts do not believe that back washing is adequate for DE filters; instead, they advise individual rinsing by hand.
  
  Cartridge filters are the easiest to clean. Simply remove the filters every two weeks and rinse them with a high-pressure hose or soak them in a solution of water and disinfectant. Cartridge filters should be replaced every two to three years.
  
  

Trouble Shooting

• Several problems arise with pool filters. If your filter seems to be running at a high pressure, the filters are likely clogged and need to be back washed. If you find sand at the bottom of your pool, a broken pipe in the filter tank may be allowing sand from your sand filter to be deposited back into the pool; you'll need to call a professional to examine the tank, locate the leak and replace the pipe.
  
  If the powder from your DE filter is in the pool, you should remove the filter grids and inspect them for holes or tears. If it seems like your pool is cloudy or dirty, you may need to replace your filter medium or backwash the system. A dirty pool could also mean a problem with the level of chemicals or the circulation system.