Dirt Passing Back Into Pool

If dirt or DE (diatomaceous earth) gets through the filter and into the pool, check for:

Damaged grids, laterals or cartridgesBroken manifolds or retainersBackwash valves that have bad gaskets or O-rings

Maintenance and prevention are key: When you feel a backwash valve becoming difficult to turn, do a teardown and lubricate before any leaks occur. While you’re at it, carefully examine grids, laterals, cartridges, and manifolds each time you break down a filter for cleaning. Don’t be in a rush when reassembling—sloppy and careless reassembly after cleaning is the cause of most filter leaks.

Filters and Backwashing

While each type of filter will keep your pool clean, the key to keeping it that way is by making sure the filter is the correct size and is regularly cleaned. So, what’s the best type of filter? The one you’re most likely to keep clean. Cartridge filters are often a popular choice because they are easy to maintain. Choose the filter that fits the size of your pool. Backwashing a DE filter should be considered a temporary solution when a complete teardown and cleaning aren’t practical. A sand filter works well with backwashing. Since there is no DE to add, it removes the potential for errors that may result in a dirty pool.

How to Backwash a Filter

Instructions vary according to your filter type; it’s best to consult the website of the filter manufacturer, if possible. Basically, this is how it is done with a DE filter:

How Often Should You Backwash?

Backwashing and teardown depend on how often you use your swimming pool and just how dirty it actually gets with normal use. DE filters are usually torn down and cleaned at least six times per year. Unless your pool gets really dirty, you should not need to backwash it beyond your scheduled maintenance. Another theory recommends to backwash when the pressure gauge is about 8 to 10 psi (pound-force per square inch) over the starting level. Also, backwash if a major storm or weather event has occurred in your region or a there is a major algae outbreak (any color). Sand filters, however, can be backwashed once a month and are typically torn down two times per year. To backwash a sand filter:

Saving Energy

You can save energy by running the pump at a lower speed after cleaning the filter. This can be achieved without reaching a point of no-flow or low-flow.

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