Swimming Pool Filters
Pool filters are the hardest worked piece of equipment on your pool.
Pool filters work round-the-clock to filter impurities so you can
enjoy pure water. You'll want a durable pool filter that will remove
even the smallest debris and sediments from your water. Here is
some helpful advice for picking a pool filter.
Sand Filters
These filters use - you guessed it - sand filtering medium. Sand
filter look like large balls and they hold hundred of pounds of
pool-grade sand. Basically, water flows into the top of the filter
housing and makes its way down through the sand bed where the sharp
edges of the sand catch the dirt. On a micron-to-micron comparison,
sand filters remove the least amount of dirt – particles as small
as 20 to 25 microns. But again for a time, the dirt left
behind contributes to the filtering process. Sand filters certainly
are efficient enough to keep just about any pool clean.
To keep a sand filter working, depending on the size of the filter
you must clean it as often as once a week during swimming season.
Maintenance means backwashing where the flow of clean water is reversed
back into the filter. The problem with this, however, is that backwashed
water is simply wasted. A typical backwashing session can waste
a few hundred gallons of water – water that must be replaced in
the pool.
Cartridge Filters
Cartridge filters have been around for some time, but they seem
to be gaining in popularity in many parts of the country. They consist
of a tank that houses three or four cylindrical filtering elements.
The filters are actually made of polyester or some other material
that can provide a superfine filtering surface. The fabric catches
and holds the impurities until you clean or replace the filter.
The cartridge can filter out anything down to about 5 to 10
microns in size. A grain of table salt is about 90 microns;
anything below about 35 microns is invisible to the naked eye. It
is important to remember that with any filter a small amount of
dirt actually aids the filtering process. In most areas cartridge
filters are less expensive than diatomaceous earth filters but cost
more that sand filters. However cartridge filters are more popular
because of the minimal maintenance involved. Some families will
find it sufficient to simply hose off the cartridge filter a few
times during swimming season to keep them working properly. Others
may need to soak the filters in detergent or replace them. In any
case, maintenance takes only a few minutes to the filtration system
in top shape.
Diatomaceous Earth Filters
DE Filters, these products can filter out dirt as small as 3
to 5 microns. If you opened the tank of a DE filter it would
look somewhat similar to a cartridge filter. But the grids are packed
with diatomaceous earth, a powder made up of billions of fossilized
plankton skeletons. It is the powder that actually catches and holds
the dirt.
DE Filters are usually the most expensive type, and they get your
pool water cleaner than the other filters. But the necessary maintenance
can be a drawback for some homeowners. Most manufactures call for
backwashing to clean the filter. In backwashing, the system reverses
the flow of water. The clean water cleanses the filter. The dirty
water is drained from the system. |
