I've brewed extract for 20 years. I've been living in my current house for the last 12 of those 20 years. My extract brews always tasted great.
Until now, I've never had any reason to question the quality of my well water for brewing.
But, a year ago I finally switched over to all-grain brewing. I've brewed a half dozen or so all-grain batches and no matter how hard I've tried, my mash efficiency has been horribly low. I've been discussing this problem with other homebrewing friends and may post a thread specific to that problem, but that's not the purpose of this thread.
At the advice of many, I sent a sample of my water to Ward Labs for analysis. Here's the report I got back. Now, I know NOTHING about water chemistry. As I said, my water tastes good and have never had a problem with extract batches.
My question is this: Is my water the cause of my poor mash efficiency?