How To Select The Best Drinking Water Filters Or Other Water Treatment Method 

— Your Drinking Water —
Are you concerned about the purity and safety of your drinking waterConcerns about the purity and safety of your drinking water
Are you confused by all the different water treatment methods availableThere are many different water treatment methods for your home
Do you wonder which contaminants are in your tap water - how can you tellWhat contaminants are in your tap water and how can you tell
Do you know which home drinking water treatment method is best for youBased on your water contaminants, is Distillation, Reverse Osmosis, Activated Carbon Filters, UV, or Bottled Water best
(Distillation, Reverse Osmosis, Activated Carbon Filters, UV, Bottled Water, orDrinking water treatment methods include, Distillation, Reverse Osmosis, Activated Carbon Filters, UV, Bottled Water)
Are you alarmed about contaminants your children might be drinkingAre there water contaminants your children are drinking
Are you or a member of your family pregnantDrinking water and risks to pregnancy

The purpose of this web site is to help you decide on the best water treatment system for you and your family.  I have tried to provide the most accurate, unbiased information possible about drinking water contaminants you might be exposed to, their health effects, and the different Point Of Use (POU) water treatment strategies available. 

There are LOTS of exaggerated claims on the Internet about home water filtration systems and other drinking water treatment methods. 

Distilling accurate information from hype can be a challenge!

Fortunately, the drinking water treatment needs for most people,
particularly those using municipal water, are often fairly simple.

The Bottom Line:
First you need some understanding of which contaminants are in your water. If you are on municipal (public) water, most water companies are required to provide an annual water quality report. EPA, NSF, EWG
There are only three main point of use water treatment methods - Each process has its benefits and limitations:
1 - Distillation is the most effective, slowest, most expensive water treatment method, and requires electricity or other energy source.
2 - Reverse Osmosis (RO) is effective against most inorganic contaminants but requires activated carbon to reduce some organic contaminants. RO requires moderate to high water pressure, is fairly slow and typically wastes more water than it treats
3 - Solid Block Activated Carbon (SBAC) is the least expensive process, easiest to maintain and does not require electricity or high water pressure. It significantly reduces chlorine, a wide variety of organic contaminants like disinfection byproducts and can be designed to reduce levels of some inorganic chemicals like lead and arsenic. Activated Carbon is ineffective against many inorganic contaminants like salts, iron, fluoride, aluminum, calcium, etc. My recommendation for most people on municipal water.
  - There are other water treatment methods, KDF, UV, ozone, activated alumina, sediment filters, ion exchange, granular activated carbon & boiling, but they have limited effectiveness and usually need to be combined with other methods.  A brief summary of other water treatment methods.
  - There is no reliable, reproducible evidence to support any claims that water can be treated in some manner —  with ionization, pi mag, oxygenation, hydrogenation, various catalysts, vortexes, magnetism, microclustering, homeopathic succussions, chi generators, intentions, photons, etc. — that will change its physical characteristics or energy levels so that it has more beneficial effects on the human body than regular, untreated water.  More information
There are no federal regulations regarding the effectiveness or design of water treatment products. The FTC has created "truth in advertising" rules, but they apparently are not enforced except in extreme circumstances. Companies are pretty much free to make exaggerated, unsupported claims to promote their products. You are ultimately responsible for selecting an effective treatment method and product.
Careful selection of water treatment products certified by NSF &/or WQA provides assurance that treatment claims are valid.

Below are 4 detailed steps that will explain the summary above and help you determine the best water treatment method or methods for your specific drinking water needs.
1. Common contaminants;  2. POU water treatment methods;  3. Contaminant reduction;  4. How to choose

    This site emphasizes treating drinking water from municipal water companies, not wells.
       Detailed information is available for those with more complicated water treatment needs.

Become informed

about the contaminants that are in your drinking water.

There are really only two ways to know what is in your drinking water:

Read the annual water quality report from your water company if you live in the United States and are on municipal water.  Your water company is required by federal law to make available reports listing the measured levels of the most common and/or harmful water contaminants.  Read a very detailed description of water quality reports.

Your water company is also required by federal law to deliver  water to your home which contains contaminant amounts that are lower than the EPA Maximum Contaminant Levels (MCLs)

Test your water.  If you have a private water source (well, spring, or surface water) you are completely responsible for the safety of your home's water supply.  This includes testing for likely contaminants, treating the water if needed, and maintaining the well, pump, pipes and treatment system. 

There Are Three Types Of Drinking Water Contaminants:
    Some of the more common or harmful inorganic contaminants include: chlorine, chloramine, lead, iron, mercury, arsenic, calcium,manganese, fluoride, copper, cadmium, sodium, nitrite, nitrate, sulfate, sulfide, chloride, perchlorate, carbonate, asbestos fibers, sand, silt, radon, radium, uranium, hydrogen sulfide
    Disinfection byproducts (trihalomethanes, haloacetic acids); Pesticides (2,4D, atrazine, hexachlorobenzene, malathion, lindane, alachlor); Solvents (trichloroethylene, tetrachloroethene, toluene, ethylbenzene, carbon tetrachloride); Pharmaceuticals, Hormones, Home & Personal Care Products (estrogen & equilenin, tetracycline & amoxicillin, ibuprofen, fluoxetine,  metformin, caffeine, N,N-diethyltoluamidet, triclosan)Other Organics (MTBE & EDB, PCBs, hexachlorocyclopentadiene & benzene, DEHP, vinyl chloride, acrylamide); Organic Particulates (plant, and animal fragments, algae); Odor/Color Causing Organics (VOCs tannins and humics); Volatile Organic Chemicals (VOCs are those organic compounds that evaporate oe vaporize easily); and so on...
    Enteric (intestinal) Viruses; Bacteria (Legionella, coliforms - including E. coli, etc.); Protozoans (Cryptosporidium, Giardia lamblia, etc.)
Fortunately, most people on municipal water do NOT have a lot of harmful contaminants to worry about in their drinking water!
inorganic chemicals, lead, iron, mercury, arsenic, nitrites, nitrates, asbestos If your water is treated and distributed by a water company, it will probably contain:
   Disinfectants are typically not harmful by themselves, but they can affect the taste and odor of your water and they create the disinfection byproducts. (chlorine and/or chloramine).
Disinfection Byproducts can cause Liver, kidney or central nervous system problems; increased risk of cancer (which include the trihalomethanes like chloroform).  
inorganic chemicals, lead, iron, mercury, arsenic, nitrites, nitrates, asbestos If your home is less than 5 years old, or has lead pipes (or copper pipes with lead solder), or has  faucets or fittings of brass, or your water is naturally soft or acidic, or corrosive, a possible and serious drinking water contaminant might be:
  Lead is a serious threat to human health and can adversely affect almost every organ in the human body.  Children are especially susceptible to lead poisoning because they absorb and retain more lead in proportion to their weight than adults. This page contains additional information about lead.
inorganic chemicals, lead, iron, mercury, arsenic, nitrites, nitrates, asbestos If you live in an agricultural region,  potential harmful contaminants include:
   Infants below the age of six months who drink water containing nitrate (and nitrite) in excess of the MCL could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue-baby syndrome.
Pesticides - a variety of insecticides, herbacides, fumigants, etc. that can cause a wide range of human health problems including liver, kidney, reproductive, neurological damage, and increased risk of cancers.
inorganic chemicals, lead, iron, mercury, arsenic, nitrites, nitrates, asbestos Young infants or children, women who are pregnant, the elderly, and people with compromised immune systems are at higher risk from many drinking water contaminates! 
Read about these risks.

There are many thousands of potential contaminants, both natural and synthetic.  A list and description of some of the more common and/or harmful contaminants that can be found in drinking water can be  Found Here. 

The lists of contaminants on this page does not mean that all drinking water contains them.  Fortunately, any given water supply will probably contain just a few (if any) harmful contaminants, but it is important to have an idea which ones before purchasing a water treatment solution.


Water Problem Table
Identify Common Water Contaminants by Their Sensory Clues

Important Introduction

Blue to Blue-green
Cloudy, or Milky
Reddish - orange
Dark brown to Black

Deposits, Spots, & Sediment
Soap scum 
Bathtub rings
Scaly, whitish
Spots on clothing
Spots on dishes
Spotting, mottling,  of
Red - brown slime
Black - brown slime
Reddish - brown
Blue-green stains
Brown-red stains
Black stains
Blackening and
   pitting of metal
   sinks and fixtures
Gray stains
Yellow stains

Salty, brackish
Sharp chemical Alkaline
Salty, brackish
Sharp chemical
Sweet, perfume
Rotten eggs
Oil or gas
Musty, earthy


about the benefits and limitations, of the POU water treatment methods.

There are thousands of brands of POU drinking water treatment systems from hundreds of manufacturers.  You see them in shopping malls, discount stores, hardware stores, and mail order catalogues - and, of course, on the internet.  Prices range from around $20 to thousands of dollars.  

There are only 3 main (POU) home drinking water treatment and purification technologies, distillation, reverse osmosis and solid block activated carbon (SBAC), each with its strengths, limitations, and associated costs.  Some treatment units use several technologies combined. 

It is worth mentioning here that there is no reputable scientific evidence that supports the numerous claims you will see that specialty water treatments (ionization, oxygenation or exposure to magnets, vibrations, photons, vortexes, thoughts or catalysts, etc,) can change the structure, chemistry or energy of the water molecules or endow them with special health benefits.  More details can be found here, here and here.

Pop-up descriptions of each of the water treatment methods are available by clicking on the link (if Java is enabled).  To save time, if you plan to read descriptions for more than just one treatment type, leave the pop-up window open, click back on this page, and click on another treatment method.

If you want to read through all the treatment descriptions and limitations at once or if Java is turned off, you can find a full description here.

    Activated Carbon
       Solid Block Activated Carbon (SBAC) filters - Specific Recommendation
       Granular Activated Carbon (GAC) filters   
    KDF filters
    Activated Alumina
    Other types of filtration systems (KDF, sediment, ceramic, etc.)

Reverse Osmosis (RO)


    Ultraviolet Light (UV light)   
    Chlorination (Not usually a POU solution.  Included because it is an important disinfection method)
    Disinfection Byproducts

Ion Exchange (Not usually a POU solution.  Included because water softeners are so common)

Bottled Water is also available from a staggering number of companies that produce
    a vast range of products including:
    Distilled Water
    Natural Spring Water (including Artesian)
    Mineral Water
    Well/Ground Water
    Purified Water
    Sparkling Water (Contains CO2)
    Flavored/Sports/Vitamin Water
    More than a few brands are simply filtered tap water.  Some bottled water is untreated, but most
    companies use one or more of the treatment methods above to purify the water before bottling.

"Altered" Water (oxygenated, magnetic, vortex, and clustered water to name a few).  


Discover which contaminants are reduced

by the main Point Of Use (POU) water treatment methods.
(Selecting inappropriate technologies can result in inadequate purification and/or spending too much money)

 The table below just lists those contaminants commonly found in municipal drinking water.
A much more complete water treatment table can be found here for those who need it.

The extensive list of qualifications (Ev, Evg, E, Add, etc.)  in the table below is a reflection
of the fact that each water treatment technology has its strengths and weaknesses.
There is no single, best drinking water treatment method for every situation.

Also, extremely important:  The same technologies from different manufacturers can
have very different contaminant reduction capabilities - certification is important!

Effectiveness Of Water Treatment Method

harmful contaminant
* harmful at high levels  
  Disinfection Chemicals
     chlorine Ev Ev Ev - Er E - - E Add - - - Eb Eb
     chloramine Edv Edv - - Er E - - S Add - - - Eb Eb
  Positive Ions
     copper *+ - - - - Er E - - Con - S - - Eb Eb
     calcium - - - - Er E - - Con - E - - Eb Eb
     magnesium - - - - Er E - - Con - E - - Eb Eb
     lead + Edv Edv Es - Er E - - Con - S - - Eb Eb
  Negative Ions
     nitrite & nitrate = - - - - Er E - - Con - - E - Eb Eb
     fluoride * - - - - Er E - - Con - - - E Eb Eb
 Organic Compounds
  Disinfection Byproducts
     trihalomethanes Edv Edv - - S - -


E Cr - - - Eb Eb
     haloacetic acids Edv Edv - - S - - Etc E Cr - - - Eb Eb
  Pesticides = Edv Edv - - Er E - Etc Con - - - - Eb Eb
 Biological Contaminants - not usually in municipal water
  Bacteria/Viruses - - - - -   E E E E - - - Eb Eb
  Cryptosporidia/Giardia E - - - E E E E E - - - - Eb Eb
 Approximate price 
 per gallon
  harmful contaminant
   * harmful at high levels  
A more detailed treatment table

Key  Description
    -  Not effective or not recommended for reducing the level of a contaminant.
   E  Effective at reducing the contaminant level.
   Eb  Effective - bottled water quality is entirely dependent on the quality of the company producing
 it.  At  minimum, it must meet quality requirements that are equivalent to those for tap water.
   Edv  Effectiveness at reducing the contaminant level depends on design & volume of the filter media.
   Er  Effectiveness at reducing the contaminant levels depends on the characteristics of the reverse
 osmosis membranes, the specific contaminants in the water and their concentrations, and the
 water pressure.
   Ev  Effectiveness at reducing the contaminant level depends on the volume of the filter media. 
 A filter with a larger volume of filter media will reduce contaminants better than smaller filters.
   Etc  Effective - Ozone treatment oxidizes many organic chemicals and transforms them into smaller
 molecules,  creating nontoxic or toxic byproducts depending, in part, on ozone exposure and the
 the original organic compounds.  
   S  Somewhat effective at reducing the contaminant level.
   Con  Contaminant can be concentrated by the treatment method.
   Add  Specific contaminant added to the water by the treatment method.
   Cr  Treatment method creates new contaminants in the water.
   +  Lead and copper are not frequently in water that leaves the municipal water treatment plant.  If
 the water is corrosive, minerals (frequently lead and copper) can leach out of a home's plumbing
 and fixtures.
   =  Nitrites, Nitrates, and Pesticides are not typically in municipal water.  These compounds are
 regulated by the EPA, and if the water company is in compliance the levels should be below the
 EPA's MCL.  There will probably always be some companies, however, that are out of
 compliance, particularly in heavily agricultural regions.  The water quality report should have
 information about whether these contaminants are a problem in your water.


 There are many specific organic chemicals in each of these categories, many harmful, many not.
 The Key simply indicates treatment methods that are listed in the literature as effective against
 representative compounds or stated as a treatment method of choice.  Check with the specific
 manufacturer (or certification organization) about specific contaminant removal.


 Cation exchange - Water softeners use cation exchange to replace positive calcium and 
 magnesium ions with a different ion (usually sodium) that does not cause the problems of mineral deposits and other nuisances. 

The table and descriptions above provide a good overview of the benefits and limitations
of the treatment methods for simple water problems, but a more extensive discussion of water treatment methods can be found here.

It is also possible, though thankfully rare, for harmful bacteria or other pathogens to find their way into drinking water from a municipal water source.  If these organisms are in the water illness can occur.  If tap water is regularly suspected to contain harmful pathogens, there are several point of use treatment options that can be considered for home drinking water.
Distillation - A good distillation system effectively removed all pathogens.
Solid block activated carbon or reverse osmosis filtration (to reduce non-living contaminants and turbidity) followed by UV or ozone treatment to kill the pathogens.

Distillation is probably more expensive than filtration and UV/ozone treatment.  

Bottled water is a good emergency source of safe drinking water, but often, by the time a problem has been discovered and an emergency boil order has been issued, many people have already been exposed to the contaminated water.  A better solution for municipal water (or well water for that matter) is to install and maintain a permanent treatment system for all water consumed in the home (including tooth brushing).  Reusable bottles can then be carefully cleaned and filled with the home-treated water to drink away from the home.


Decide on the best treatment method
for your specific needs.
Things to Consider when Selecting a Purification Solution:
How much purified water you would like to use per day for drinking and cooking and watering pets and plants (a family of four can easily use 3 to 6 gallons per day).
Which contaminants are actually in your water (and which ones might occasionally show up). The only way to know this for sure is to request a report from your water supplier or have your water tested.
Which contaminants you are interested in removing (the information in the other areas of this site should help). The plan I adopted was to go with a solution that provides the best protection from most of the potential contaminants (for the lowest cost and least maintenance) - even though most of the contaminants are not currently, and hopefully will never be, present in my tap water.
The cost of the solution you decide upon, both the initial cost (which may be relatively high for some filtration systems, ion exchange units, distillers, etc.) and the ongoing costs (which might be high for distillers, bottled water, pitcher/faucet filters, etc.).  

Treating your water is probably not something you will do for a few months.  Providing safe, good tasting water is typically a long term commitment.  Look at the total amount you will spend over the next 10 to 40 years based on the amount of pure water you would like to be able to use for drinking, cooking, washing food, etc.
The overall value of the product. Is the product certified to perform as advertised (or in the case of bottled water, is it certified to be free of contaminants). Does the product provide you with safe, good tasting water at a reasonable cost.  Is there minimal maintenance required.  Is the company reputable 


Comparison of Long-Term Costs for Water Treatment:
Most people, when they make the decision to invest in a

Have you considered how much it will cost to obtain pure, safe water for the next 5, 10, 20, or even 40 years?

When you decide to protect yourself and your family from drinking water contaminants, 40years may seem like a very long time to think about treatment costs.....

  However -

If you plan to use just 10 gallons of purified water a week (less than 1.5 gallons per  day), the water treatment method you select can mean the difference between  spending about $1,700 over 40 years or spending more than $31,000 for pure, safe, good tasting water!

 This link will enable you to compare the long-term cost of various types of water treatment options based on the amount of water you use (or plan to use) per week.


My Recommendations for a POU Water Treatment Solution:
About Me

The most important consideration for selecting a water treatment solution is that the treatment method effectively reduces the contaminants of concern in your water.
Always check the manufacturer's certified contaminant reduction table to make certain any treatment method you are considering will significantly reduce the specific contaminants you are concerned about!

The suggestions below are in order of my preference. The criteria I use for ranking the methods are:
  the best performance (the product effectively reduces contaminants of concern), 
    at the lowest price (initial + ongoing costs), 
    with the least maintenance
    for the longest life.

1) Solid Block Activated Carbon (SBAC) filtration system - A high quality SBAC water filter will provide decades of service for a treatment cost of typically under $0.10 per gallon, and it will require minimal maintenance (a periodic cartridge change) and no electricity use.  Highly Recommended if your water treatment needs are met by the characteristics of these filters.  Most municipal water is effectively treated by SBAC. 

This page provides details and ordering information on an excellent value SBAC filtration system that my family and I have used since 1996.  These were the highest rated under counter filtration systems by Consumer Reports in 2012 and again in 2013. 
2) Reverse Osmosis - Recommended in situations where the water contains contaminants of concern, like nitrates, salinity, and/or those heavy metals that can not be reduced by activated carbon.  A high quality activated carbon filter should be part of the package to reduce organic compounds not removed by RO.  The cost per gallon is about double SBAC, and there is somewhat more maintenance involved. Electricity is not ordinarily required for proper functioning, but relatively high water pressure is.  Details on a good RO system with an excellent SBAC post filter can be found here.
3) Distillation - Recommended in situations where the water contains contaminants of concern, like nitrates, salinity, and/or heavy metals that can not be reduced by activated carbon.  Distillation is an excellent, highly effective water treatment solution for "really ugly" water.  The reason I do not highly recommend it is because distillation is typically a slow process (requires hours to treat several gallons of water), around twice as expensive as RO (about 4 times more expensive than SBAC), and most systems require electricity to operate - when the power is out they are completely useless. This page addresses the various misrepresentations about distilled water.

Quick summary of other water treatment methods:
A complete description can be found here

A) Ultra Violet (UV) Light - Not recommended as a single, stand-alone water treatment solution because it is only for killing biological contaminants and does not reduce other harmful contaminants that might be in the water.  A good option, however, to provide additional protection for water filtered by a good activated carbon or RO filtration system to kill bacteria and viruses that may make it through the filters.
B) Bottled Water - Usually a good choice for safe water, excellent for emergencies, but most is very expensive compared with other alternatives ($0.25 - $6.00 or more per gallon). Bottled water, unless you fill your own bottles, will unnecessarily waste resources.
C) Granular Activated Carbon (GAC) counter-top or under-counter filters - Usually better than nothing if manufacturer recommendations are followed.  Large pore size and granular nature of the filter media make them less effective at contaminant removal than a SBAC filter.  They are, however, usually much less expensive than SBAC systems.
D) Faucet- Mount Filters - (Can be SBAC or GAC) - SBAC faucet-mount filters typically have a pore size of about 1 micron - able to effectively reduce cysts.  They are smaller than most counter-top or under-counter SBAC filters and therefore not as effective for contaminant reduction at the same flow rates.  GAC faucet-mount  filters have essentially the same effectiveness as Pitcher Filters.  Both kinds have relatively expensive replacement cartridges that do not last very long and can easily cost more after several years of use than a more expensive, more effective SBAC system.
E) Pitcher Filters - Better than nothing and most will reduce chlorine and sometimes lead to acceptable levels.  Large pore size and relatively small amounts of granular media make them ineffective for effectively reducing the levels of many  contaminants.   Relatively expensive replacement cartridges do not last very long and can easily cost more after several years of use than a more expensive, more effective SBAC system.
F) Water Softeners - Reduce hardness (calcium and magnesium ions) and usually add sodium ions.  They are mostly ineffective against other contaminants of health concern.
G) Sediment Filters - Good for what they are designed for - removing particles from water - No other contaminant reduction takes place.  They are often used as a pre-filter for more expensive filtration systems to keep them from becoming clogged.
Ceramic filters
with a very small pore size (around 0.2 micron) are a special case of sediment filter and can be used in emergency situations to significantly reduce biological contaminants from water.  They are ineffective against chemical contaminants or viruses.
H) KDF Filters - A granular filter media which is promoted as changing free chlorine into non-irritating chloride, for reducing bacteria, and for precipitating some heavy metals like lead.  Works with hot water, and is often used in shower-head filters and in combination with activated carbon in household filtration systems.
 I)  Boiling - Effective for emergency disinfection of water only.  Pathogens are killed and volatile contaminants may be driven off, but many contaminants will remain.


Please be advised that the information on this page and on this site is for general educational information only and is NOT intended to make any specific health claims or recommend any specific treatment method or preventative advice for any health issue or problem.  Consult your physician or a health specialist for specific steps to take for your specific health requirements!

Copyright 2005 Randy Johnson. All rights reserved.TopUpdated 11/11/2013

Topics On
This Page

Drinking Water

Water Problem Table

Point of Use
Water Treatment Methods Description

Reduction by Treatment Method

What is the Best Drinking Water
Treatment Method
For You

SBAC Filter
Reverse Osmosis

Summary of Other

Bottled Water
GAC Filter
Faucet Mount Filter
Pitcher Filter
Water Softener

Sediment Filter
KDF Filter

External Links

Drinking Water Information

About Me


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