I've done some searching around this site and can find some forums where some posters praise water filters and warn against the evils of fluoride - but there seems little evidence presented backing up what makes for a good filter. Mark posted on how bottled water is not much better than tap and to beware of plastic contained beverages. He also said to get "a cheap water filter". So is a cheap water filter, any old one, the one to get?

This seems a highly nuanced subject where you need to get your head around what is good for the body in water, what is safe and possible with technology to change water, what measurements of stuff in water means, etc. Can someone point me to someone that discusses this from a paleo or primal perspective that is skeptical of Conventional Wisdom (and the health authorities)?

For example....see the below on Flouride removal from Aquasana. It basically says that flouride removal is a good idea... but! 100% removal requires aluminum filters that may be harmful to health so they use a different method (ion exchange) that only cuts a large portion out. What is weird is the flouride article used to be on their US site, but I cannot find it there anymore, only on their AU site... hmmm...

I was considering a Cuisinart CHW-11 with built in filter, but was not sure how to judge the quality. I know people rave about Berkey. Aquasana has some pages that sounds good, but is it right or hype? I'll post below some of the issues to solicit feedback....

Fluoride Removal | Aquasana: Pure Water Filters
Fluoride Removal
The Aquasana reduces fluoride by 40-60%.

There are 5 isotopes which make up fluoride and the Aquasana will remove two of the isotopes with the ion-exchange technology. This reduces the influent levels to approx. 0.5 ppm.

All research showing negative effects has shown levels above 1 ppm.

Some water filters which remove fluoride contain alumina as their filter media, which is not recommended because fluoride has a strong affinity for aluminum, forming aluminum fluoride. It ‘tricks’ the body into thinking it is a hydrogen atom, allowing it access across the blood-brain barrier. . Research has shown a link between aluminum fluoride and kidney damage as well as brain cell damage, such as lesions in the brain similar to those found in Alzheimer’s and other forms of dementia.

Which 2 isotopes from fluoride are removed and what information do you have on them?

Calcium fluoride: Also known as mineral fluorospar (fluorine – semi precious gemstone) which is found in nature as a solid and is insoluble in water. It is commonly used as a window and lens material, in the manufacture of Teflon and in the separation and concentration of uranium isotopes in nuclear reactors.

Sodium fluoride: A colourless crystalline salt used in the fluoridation of water, toothpaste, as an insecticide and rat poison. According to Hazard Identification Data it is listed as toxic if swallowed or inhaled and affects the respiratory system, heart, skeleton, circulatory system and kidneys. Long term exposure may cause mottling of teeth and brittle bones (fluorosis), weight loss, anaemia, calcified ligaments, general ill- health and joint stiffness.

References:
Worksafe Australia (1996), Hazardous Substances Sodium Fluoride
Lange, A (1946) Handbook of Chemistry, Handbook Publishers, Inc, Sandusky, Ohio,USA
Agency for Toxic Substances and Disease Registry (1993), ToxFAQS Fluorides, Hydrogen fluoride, and Fluorine.
full Q&A at Aquasana Water Filters - Frequently Asked Questions about Water Filters (could not fit here)
Question: Is Chlorine harmful?
Answer: Chlorine was first added to a community water system in 1908 in Chicago and was instrumental in eliminating many types of water-borne disease such as Cholera and Typhoid fever. Prior to chlorination, many major cities had death tolls of 1 in 1000 people from Typhoid alone. Chlorine has been used to disinfect municipal water for over 80 years and has had some positive effects on public health. In the 1970's it was discovered that chlorine, when added to water, forms Trihalomethanes (chlorinated by-products) by combining with certain naturally occurring organic matter such as vegetation and algae. In 1992 the American Journal of Public Health published a report that showed a 15% to 35% increase in certain types of cancer for people who consume chlorinated water. This report also stated that much of these effects were due to showering in chlorinated water. The National Cancer Institute estimates cancer risks for people who consume chlorinated water to be up to 93% higher than for people who do not. The effects of drinking chlorinated water have been debated for decades. However, most experts now agree that there are some significant risks related to consuming chlorine and chlorinated by-products in drinking water.
Chlorine and Cancer

Question: Why do some areas test negative for chlorine?
Answer: Virtually all city water systems contain some level of chlorine. The level will vary based on outdoor temperature, the season, distance from water utility and current usage. While chlorine may sometimes be undetectable on a certain day with a standard OTO test kit, that level can change dramatically day to day. Also some cities use ammonia at certain times as a disinfectant in order to reduce chlorination by products. Without chlorine the dangers of water borne disease would be too significant. An undetectable chlorine level, on a certain day, does not eliminate the need for an effective home filtration system.

Question: What is the best container for storing filtered water?
Answer: Glass is always best, however if glass is not practical, then a high grade polycarbonate material is best. Clear plastic bottles and pitchers with a #1 in the recycle triangle on the bottom, like the bottles used by Evian and the higher quality bottled waters, are the best option for water storage since they have been shown to release the lowest levels of plastic component chemicals into water. Translucent, colored or bottles with a number other than 1 on the bottom should be avoided because there is the possibility of higher levels of chemicals leeching into the water from the plastic.

Question: Are whole house systems (P.O.E.- point-of-entry) better than counter-top filters (P.O.U.- point-of-use)?
Answer: P.O.U. systems are by far the best way to ensure the highest quality water since many water-borne contaminants come from the plumbing in your house, especially lead and vinyl chloride from the piping. By filtering water at the point-of-use you remove contaminants just prior to consumption, eliminating the chance of recontamination. Point-of-entry systems offer certain benefits but do not replace the benefits of point-of-use filtration.

Question: What are the benefits of magnetic water treatment?
Answer: While there are manufacturers that make beneficial claims for magnetic water treatment, there are no credible studies or documentation that magnetics offer any measurable benefits for drinking water, consumers should beware of undocumented claims.

Question: How do you know if there are contaminants in your water?
Answer: All public water systems contain some level of one or more unhealthful chemicals. Regulations only require periodic testing of about 90 chemicals. There are now more than 75,000 chemicals used in our society with over 1000 new ones being developed each year. Contaminant levels fluctuate throughout the year making it impossible to know the actual level of contamination in a central water system. So far over 2100 toxic chemicals have been detected in America's water systems. The risk is high; the cost for a sure solution is low, 10¢ per gallon with Aquasana.
See What's in my water?

Question: Are some people more sensitive to chemicals in drinking water and shower water than others?
Answer: Definitely, small children and the elderly are especially more affected by contaminants in water due to a reduced capacity to deal with toxins and an under-developed or less tolerant immune system.

Question: If my municipal water company's Annual Water Quality Report shows that it meets all EPA guidelines, does that mean its safe?

Answer: On October 1st 1999 a new federal law went into effect that requires water utilities to send each customer a detailed report showing what is in their water, appropriately called "The Right To Know Amendment." The most important thing to remember is that no matter how insistent these reports are that "contaminants in your water do not necessarily pose a health risk", any level of contamination in our drinking water does in fact represent a danger to our health. Of the over 75,000 toxic chemicals used in our society, the EPA has only set standards (MCLs) for about 90, and those 90 Maximum Contaminant Levels are not necessarily set on "health effects." The EPA considers limited health studies based on consumption of one certain chemical by a 175 lb. adult when setting these standards. No consideration is given to the effects on small children or the combined effects of two or more contaminants, which some studies show are magnified by as much as 1000 times. Water utilities are only required to test for the 90 contaminants that the EPA has set standards for.
(edited for length).