Our neighbor has a kitchen water filter and her water tastes better. What types
of water filters are best for flavor and safety and do they cost much to operate?—Ann
Even if your water is from a public supply, it may still
contain small amounts of contaminants. There’s always a possibility that by
the time the water reaches your house, the chlorine level may have often dropped
to the point where it may have gotten reinfected en route. It may not be a bad
idea to first have your water tested.
Although there are many specific models, brands, and trade
names of water filters, the basic options can be broken down into distillation,
reverse osmosis (RO), ozone, ultraviolet light (UV), and carbon. Each type has
its advantages for improving various water problems.
Countertop electric distillers are effective for improving
most common water problems and removing most contaminants. Since the water boils
during the distillation process, it is also disinfected. The water vapor condenses
and drips into a gallon jug. Once the jug is filled, store it in your refrigerator.
RO systems are also effective for most common drinking water
problems, and they produce filtered water as you use it. This eliminates the
chances of recontamination when the filtered water is stored.
These units use an RO membrane that acts like a super-sieve
to filter out almost everything in the water. Most units also have pre- and
post-carbon filter cartridges to remove chemicals. The only drawback is that
these units use more water than is actually purified, so some water is wasted.
Ozone gas purifiers are extremely effective and leave no
residual chemicals in the water. Many municipal water plants now treat all their
water with ozone gas. In addition to killing bacteria, cysts, and viruses, it
improves the taste. Ozone quickly dissipates from the water, so there are no
harmful health effects from it. UV purifiers pass an intense light beam through
the flow of water inside the unit.
Small portable ozone purifiers are also ideal for camping
or during emergencies. Hang the tube and bubble stone into a jug of water and
switch it on. Another good use is to purify and clean fresh fruits and vegetables.
Fill your sink with water, then place the food and bubble stone in for a few
Carbon filters improve flavor and remove some chemicals.
To filter out impurities, a solid carbon block is better than a granular carbon
filter. Granular ones are often used as post-filters for other types of filters.
Consider a mini-RO unit (quick-disconnect aerator) for use on kitchen faucets.
The important thing to remember for a water filtering system
that uses a replacement filter is to replace the filter when it is time. Most
systems provide some type of indicator.
The utility bills cost to operate a water filter depends
on the specific design. Distillers, since they use electricity to boil the water,
will push up your electric bills the most—about 25 cents per gallon. In the
winter, this electricity ends up as heat in your house, so the net cost is much
lower. In the summer, use it in your garage or other unconditioned space.
Ozone generator units use a small corona discharge ozone
generator. To purify one gallon of water, it is recommended to run it for 15
minutes. At only 24 watts, this costs less than a penny per gallon. Ultraviolet
water purifiers also use only about 30 watts of electricity. Many replacement
carbon filter elements are priced in the $20 range.