In the particular section of the city I live in, the tap water has a poor taste. I use a Pur brand water filter (edit: activated charcol filtration) which improves the taste significantly (although it is still poor relative to bottled water).
For extract brewing, I purchase 6, 1-gallon water jugs from Wall-Mart. This adds roughly $10 to each batch.
I should hopefully begin All-grain brewing soon enough, and wanted to switch to filtered tap water in order to reduce cost.
I've been able to locate the mineral composition of the water for my section of the city.
By filtering my water through the consumer water filters, will the mineral composition of the tap water be altered, rendering the information I have gathered useless?
Edit -
In Brewing Classic Styles by John Palmer, he states:
Charcoal filtration alone will not affect dissolved minerals like iron, calcium, magnesium, coppe, or bicarbonate.... Most carbon filters are highly effective at removing chlorine and chloramine...
(pg 26)