These systems are sold for around two hundred dollars with stainless steel tanks and a better flow rate. However, the heart of the system is gravity, which is still to this point, free. The most expensive item you will need and that you probably won't find at the big box store is the ceramic filter.
However, you can get this filter from Amazon for $22. Here is the link. A spigot is only about $6 and can probably be had for even less.
Interestingly, the story of these devices goes back quite a way. Apparently, in the late eighteen hundreds in England the drinking water was abysmal. The river Thames was polluted to the point that people were dying from drinking it's water.
There was a company there called Doulton that specialized in porcelain dishes. Queen Victoria commissioned them to create a water filter to purify the water from the Thames. And so they did. They built the first ceramic water filters for the crown and the design hasn't really changed since.
One tank sits on top of another. The contaminated water is poured into the top tank. The filter, which is known as a candle filter, because it is shaped roughly like a candle, is fitted into a single hole through both containers. So in order for the water to make it's way into the lower tank it has to seep through the ceramic filter. The ceramic pores are microscopic and it is a slow process but it filters out all of the pathogens.
It is an amazingly simple device but has the most beneficial outcome. You can use two, three, or four filters per container to process more water if needed. The commercial versions start out with at least two filters and go up to four.
So for around $30 you can have a virtually limitless supply of clean drinking water in case of an emergency.
Personally, tap water tastes flat to me. It also has chlorine and it is fluoridated where I live. There are volumes written on the problems of fluoride in the water supplies of the US. I believe that it is harmful for people since it's source is industrial waste. It is suppose to fight dental decay and if you want to read the official version just read the wikipedia entry on it. I prefer not to have chemicals in my water. There are ceramic filters available that will filter the fluoride and chlorine out of your tap water.
But to me the water out of the tap is just lifeless. I much prefer to drink rain. So I take the water that the rain barrels collect and filter it. The difference is more a subtlety than a taste issue. Rainwater just has more body than tap water. You don't really need to filter rainwater it is safe to drink already, but I run it through the filter anyway.
Most of the world doesn't have water on demand out of taps. And by the same token, the Western world holds the belief that the water that does come from the taps is safe. I don't trust it. It tastes weird, some more than others. During the time I've lived in Atlanta there have been many boil water advisories and not a single year goes by without one. The latest was only this month...
http://www.ajc.com/news/news/boil-water-advisory-parts-east-atlanta/nfWG2/
For $20 a ceramic water filter is a great investment. Having a few on hand could really be a game changer in an emergency.
