Filtering Tap Water for All Grain Brewing
Water is one of the most important ingredients in any brew. It doesn't matter how fresh your grains are and how good your hop schedule is, water can make or break the perfect beer. When I'm trying to perfect a recipe, I'll use something like the Bru'n Water calculator to distill tap water with a water report in hand to build up the intended water profile. But, for quick and easy water, here's what I go with.
It's your standard carbon filter with a drinking safe water hose and a clear hose on the other side. You might want to try going straight for reverse osmosis filtered water or even distilled water, but that would be a mistake. Those waters tend to lack the necessary minerals and ions for proper conversion in the mash (including PH) or even yeast attenuation - and frankly the final product won't taste all that great. Experimentation in this area is a fun and interesting adventure.
The carbon filter I use is on the higher end of this class of filter where it can get pretty pricey. In any event, I've done the blind taste test on tap water and it's night and day.
So, when you're throwing all of those expensive hops in there, you can at least know the water doesn't contain the common big nasties.