In A Nutshell
I’ve been reviewing water filters for about 10 years. During that time, I’ve become convinced that gravity-fed filters are the best choice for almost everyone’s filtering needs. I recommend ProPur filters, which use combination of ceramic and carbon block filtration. Overall, they are the cheapest type of filters to maintain. If you want a faucet-attached filter or a whole house filter, I recommend Pure Effect Filters — these are made in the USA by a family-run company with an excellent track record.
Here are types of contaminants you want to remove from water:
- Toxic metals (Lead, Mercury, Aluminum, Cadmium, Chromium, Copper, etc.)
- Additives (Chlorine, Chloramines, Fluoride)
- Chlorination By-Products (Trihalomethanes or THMs)
- VOCs and other Organic Compounds (Pesticides, Herbicides, Pharmaceuticals, Fuels)
- Bacteria and viruses (Giardia, Cryptosporidium, etc.)
- Radioactive substances (Radon and Uranium, etc.)
If you get municipal water through a tap, these are the most common contaminants you’ll find:
- VOCs / organic compounds
If you use well water or other non-municipal water, these are the most common contaminants you’ll find:
- particulate matter
- bacteria and viruses
- VOCs / organic compounds
- radioactive substances
The Effectiveness Of Different Types Of Water Filters
Pitcher-style filters such as Brita filters are inexpensive units, making them very popular with consumers. However, in the long term, they are actually one of the most expensive option. This is because the filters cartridges require frequent replacement — the cost for 40 gallons is $7-$10 each, or $130-$190 for 750 gallons.
Almost all pitcher-style filters use GAC or “granulated activated carbon” as the filtration medium. Typically, GAC is coconut husks that has been heated to a high temperature in the absence of oxygen (or activated) and then granulated. These types of filter do remove some chlorine and hydrogen sulfide (rotten eggs odor), but are not effective at removing VOCs, metals, pesticides or fluoride. Overall, they are not very effective water filters.
My Overall Rating: Poor
Colin Ingram, author of the The Drinking Water Book rates all pitcher filters no higher than “Acceptable”.
Filters that attach to your kitchen faucet are very similar to Pitcher Filters, but do filter a little better than the pitcher-style filters. However, they have the same drawbacks — they are expensive to maintain and they do not remove many contaminants. You must replace filters every 100 gallons at $20-$40 each or $140-$180 for 700 gallons.
My Overall Rating: Fair
Colin Ingram, author of the The Drinking Water Book rates all faucet filters no higher than “Acceptable”.
Gravity-Fed Drip Filters
In my opinion, the best water filters are gravity-fed drip water filters like ProPur (filter’s homepage). These filters are excellent at removing chlorine, chlorination by-products, fluoride, VOCs, pesticides, particulates and pharmaceuticals. ProPur filters use “candle” type filters, which are widely available and can be customized to your specific filtration needs. Their latest filter, the ProOne G 2.0, will remove fluoride — including hydrofluorosilicic acid (few filters remove this contaminant).
In my opinion, ProPur filters have a higher build quality than the more popular Berkey filters. ProPur filters are made out of 100% stainless steel including the spigot. Also, in recent years, the quality of these filter seems to have declined — there are many reports of Berkey filters breaking/leaking after a few months of use (see this page for example).
Gravity-fed filters require no electricity to operate — water is filtered as it drips from the upper chamber to the lower chamber. Because the water is filtered slowly, the filtration is much more effective than a faucet-mounted filter. Generally, slow filtration methods tend to be best.
These filters use carbon block filtration, which works by the process of adsorption (different than absorption). In this process, the carbon attracts certain contaminants at the molecular level, and the contaminants become attached to the surface of the carbon. Once the surface of the carbon is full, the filter must be thrown out and replaced. However, the ProPur filters can be periodically scrubbed, and thus reused for years.
Another advantage of this filter is that it can be collapsed and taken with you when you go on vacation.
These filter are certified to NSF/ANSI standards #42 (test for chlorine, taste, odor and particulates), NSF Standard #53 (tests for Cryptosporidium, Giardia, lead, VOCs and MTBE) and NSF Standard #61 (tests that toxins aren’t leached into water). They are manufactured in England.
Propur filters range in price from $129 to $299. They are available from Amazon.
Overall Rating: Excellent
Reverse Osmosis Filters
Reverse Osmosis filters use a membrane which removes many contaminants from water. They is usually paired with a Granulated Activated Charcoal filter to remove chlorine. Most reverse osmosis filters are installed under the sink and have a holding tank. The semipermeable membrane separates many contaminates (which usually have a larger particle size that water) from the water and rejects a large amount of water in the process. The result is a waste of several gallons of water for every gallon filtered and many naturally occurring minerals (including calcium and magnesium) are also removed from the water.
However, they are quite effective filters, in terms of removing contaminants. However, they do not reduce VOCs or pesticides (unless a Carbon Block filter is included). They can take up to an hour to filter one gallon of water and the filters need to be replaced regularly.
If you want to got this route, I recommend the iSpring Reverse Osmosis System, which is quite reliable.
Overall Rating: Very Good
Countertop distillers are effective water purifiers, but they take some time to distill water (for example 5 hours to distill 1 gallon). They also require electricity to run, and they give off some heat and the integrated fans make some noise. Also, most distillers do not remove VOCs (like benzene) because they have a lower boiling point that water. So they will vaporize together with the stream, resulting in a contaminated distillate.
Countertop distiller that get a rating of “Excellent” from Colin Ingram in the The Drinking Water Book are: Megahome Countertop Distiller, Waterwise 4000 and Waterwise 8800, Kenmore 34480 and Pure Water Mini-Classic.
Megahome Countertop Water Distiller
This distiller is sold under many brand names — it’s the most widely distributed distiller in the world. It has many quality components despite being inexpensive. It produces 1 gallon of water in 5 hours. The water is passed through a small granular carbon filter. There’s a sealed connections from the distiller to the water collection container, so there is minimal risk of contamination by air. The unit has a stainless steel boiling chamber that is easily accessible for cleaning.
The Megahome Countertop Distiller is available from Amazon for about $150.
Waterwise 4000 Countertop Distiller
This is a more powerful version of the distiller listed above. It has the same features but produces 1 gallon of distilled water in 4 hours. Also received an “Excellent” rating from Colin Ingram in the The Drinking Water Book.
The Waterwise 4000 is available from Amazon for about $280.
Overall Rating: Excellent