the water ionizer is the best one on the market, filters the contaminants out and makes the best tasting anything-you-make with it, coffee, tea, foods, and of course beer. but only for the serious water connoisseur; amateurs won't spend on it. the water is of consistent quality - that is why it has a patent.
I wrote yesterday in another thread that chloride:sulfate ratio was one of the biggest hoaxes in 21st century brewing. I didn't think anyone would have the temerity to mention water ionizers in a topic entitled Brew Science. Surely the water ionizer is the biggest hoax of all in the 21st century and probably for all time when it comes to water treatment. The magnetic softeners are perhaps the second.
Of the water ionizers the Kangen is definitely the best: for the marketer. It is sold by a pyramid structure which means that it sells for a much higher price than any of the others and also neatly protects the guys at the top of the pyramid from action by the FDA. They are the ones that make the false claims. The salesmen just repeat what the factory says. As the guys doing the lying are in Japan they are protected from action by US authorities. The lowest tier people (like catlee) are as taken in by the BS as the unsuspecting public and as they aren't the ones making the claims the government can't go after them.
There are lots of places on the net where the individual claims are debunked in detail. I'll only mention a couple of things here.
All water is ionized. At a given pH the concentration of hydrogen ions is 10^(-pH) and of hydroxyl ions is 10^(pKw - pH) where pKw is 14 at 25 °C. As we know from this forum water can contain lots of other ions. If you want to 'ionize' your water by adding the ions of salts, add the salts.
The machine works by electrolyzing the water. If the water is low in dissolved ions it will not conduct so they have you add sodium chloride. The sodium ions are reduced to sodium at the cathode which reacts with water to produce hydrogen gas and sodium hydroxide. This is the 'alkaline water' the machine produces. You can get the same thing by adding lye to water. At the anode chloride ion is oxidized to chlorine gas which reacts with the water to produce hydrochloric acid and hypochorous acid. This is the 'acid water'. By blending in various proportions you get the '5 types of water' the machine produces. In an intermediate blend the lye neutralizes the hydrochloric acid and the hypochlorous acid giving NaCl and hypochlorite ion. This, by the way, is how electronic pool chlorinators work. Rather than spending $4000 on one of these machines you can achieve the same result by adding a couple of drops of bleach to your water. $4000 or a bottle of bleach? Which is the more economical purchase?
One of the more deceptive aspects of the marketing involves ORP. They have a video in which they stick an ORP probe into brand X water and then into their alkaline water. The meter reading plumments. Of course it plummets, not because of the ORP but because of pH. ORP meters respond to pH and ORP. To calculate ORP one must measure the pH and subtract its effect from the reading. You would hardly expect catlee or the public to understand that but as HBD Brewing Science readers we do (well we don't discuss REDOX very much here it is true as most of the chemistry of water is acid/base).
Etc....
Don't be taken in by this. Certainly there is no benefit to brewing. We don't put lye or bleach in our beer!!!