This episode will show you how to "dial up" your annual city water report online so you can know exactly what's bring put into your water.
Yes, the power of the internet is amazing...
If you want to know what water filters you should be using this is the first step to take.
If you know what is making your water toxic, then you can know what to target to filter the toxins like chlorine, chlorides, turbidity, fluorides, nitrates and all the other nasty ingredients that city water plants add to our drinking water supply.
Reports only seem available for the bigger cities but try a google search such as "Minneapolis MN annual water report". I would think that your local water treatment plant would have to give you this information if you can't find it online!