New Filters are Expensive. You will save more far more by
rejuvenating than by buying filters, and the indicator compound will tell you
exactly when you need to replace the filter.
Following is a Consumer Report
Research Article Excerpt:
Filtering your tap water
gives you control over what's removed from the water you drink. Unlike
bottled water, many filters tell you exactly what they filter out. Filters
also give you clean water that's cheaper than bottled water delivered to your
home; that's about 30 to 50 cents per gallon on average vs. 89 cents to more
than $2 per gallon. A filtering system may have drawbacks, however. You must
replace filter cartridges every few months, the system may not deliver water
quickly enough when you need it and, depending on the type of system, you may
need to pay a plumber to install it.
All filtering systems
work the same way: Water passes through a removable cartridge filled with a
filtering medium such as charcoal. The systems and replacement cartridges are
sold at home centers, mass merchandisers, and supermarkets. There's a screw-on
filter for just about every kind of tap in your home--sink, shower head, and
refrigerator water dispenser--plus more elaborate systems that go under your
sink or in a basement.
For this report, we
tested 19 models ranging from $18 to $240. We spiked water with lead and
chloroform, a trihalomethane (THM), both widespread contaminants and health
hazards at high concentrations. We ran up to 240 gallons through each filter
(less for carafes, or if a filter clogged). To see how well the filters removed
off-tastes, we cooked up batches of cabbage-flavored water, ran it through each
filter, and tasted the results.
We tested five types of
systems. Two--carafes and faucet-mount filters--can be installed without calling
a plumber. We found both suitable for removing off-tastes if you don't have a
severe contamination problem. Both also shield you from spikes in lead or THM
Three other types of
systems--undersink, reverse-osmosis, and whole-house (also called
point-of-entry)--are best installed by a professional plumber or seasoned
amateur. Most were fine for filtering lead and chloroform and for improving
BEYOND THE CARAFE
The sale of carafes like the $18,
8-cup Pur Advantage CR-1500R
(left) we tested has given rise to larger siblings like the 10-cup Pur
Ultimate Large Capacity (center), up to $38, and the 1.9-gallon Pur
Ultimate Dispenser, up to $45.
CONSIDERING THE CLAIMS
All tested filters made
removal claims. Those claims are certified by National Sanitation Foundation
International (NSF), a nonprofit testing lab. To be assured a filter will remove
a contaminant, its label should specify that the filter is NSF-certified for
The filter you choose may
be certified by another testing agency, or it may not have any independent
third-party certification of performance. Having independent testing and
certification of performance certainly supports the validity of any performance
The top-rated undersink
model, the Kenmore 38460, $80, A CR Best Buy, is certified to
remove sediment, small particulates that cloud water, and cysts (formed by
parasites). Both the undersink Omni CBF-20, $170, and Culligan SY-2500,
$180, claim to remove more: the pesticides lindane and atrazine, mercury, and
asbestos. (The Omni was ranked higher than the Culligan because it
didn't clog as much.)
Some manufacturers offer
replacement cartridges, each designed to remove different contaminants. You can
use those interchangeably, if they're the same size and brand as the cartridge
included with the filtering system.
These sit in the fridge or
on a counter. Pour water into the top and it's filtered as it trickles into the
bottom reservoir. We tested half-gallon carafes, which fill in about 20 minutes.
If that's not enough water, there are higher-capacity versions (photo above).
Nearly all were rated very good or excellent at removing lead and chloroform,
which is sufficient for most people's needs. Our sensory panelists found the
Pur Advantage CR-1500R, $18, good, and the Brita Classic OB01, $20,
very good at removing off-tastes.
screw directly onto a sink faucet. When you don't need to filter, such as when
rinsing dishes, a valve lets you bypass the filter. Their cartridges last longer
than the carafes' but still must be replaced four times per year. The rate at
which they deliver water can slow with use.
The two models we tested
were very good at removing lead and excellent at removing chloroform and
off-tastes. The Pur Ultimate Horizontal FM-4700L, $43, clogged well
before its cartridge's 100-gallon lifetime; it slowed to 10 minutes per gallon
by the time it had filtered 60 gallons in our tough tests.
These attach to
the cold-water line beneath a sink. The housing can be attached to a wall or
cabinet back. Filtered water is drawn through a separate faucet. Some systems
include that faucet; with others, you may need to buy one.
All the tested models were
excellent at removing chloroform and most were very good or excellent at
removing lead and off-tastes. Compared with the faucet-mounted models in our
tests, most undersink models delivered water more quickly and were less prone to
undersink models use a special membrane to remove contaminants. Larger and more
expensive than other undersink systems, they can take up most of the space
beneath a sink. Removing dissolved minerals is their strength. Reverse-osmosis
systems deliver water very slowly--about 50 minutes per half-gallon--too slow
for most households. They also waste about 5 gallons for each gallon purified
and require periodic sanitizing with bleach.
Both models we tested were
excellent at lead removal. They were very good or excellent at removing
chloroform and excellent at removing off-tastes.
These hook up to your home's
water main, so you can use filtered water for bathing, laundry, and dishes. If
your tap water contains sediment, a whole-house system can protect your
appliances and eliminate having to periodically clean out clogged faucet
The two models we tested
weren't as effective as any of the other systems at removing chloroform. The
Kenmore 38440, $35, was quite effective at removing lead and off tastes,
while the Omni U-25, $55, was poor at both. Neither model claimed to
remove chloroform or lead. They delivered water fairly speedily and weren't
prone to clogging, although the Omni's filter cartridges last only three
The two faucet-mounted
models and the five top-rated undersink models did an excellent job of removing
off-tastes. For removing both lead and chloroform, all models but the
whole-house units are fine.
If you need help remembering
to change cartridges, look for models with a cartridge-life indicator. Those are
noted in the Ratings, as are contaminants we didn't test for that each filter is
certified to remove. If no model handles the ones you're concerned about, check
the site of other testing and certification programs including NSF at
www.nsf.org, UL at
www.ul.com, and WQA at
www.wqa.org for models that do. You may need to search for drinking
water treatment units.