I brewed my first all-grain batch and hit 82% efficiency, using hard water from a friends well. The last two batches I've done, I used the soft city water from my home. On both of those runs I've seen about 65% efficiency. The crush looked to be the same on all batches and all brewes were similar, all wheat beers. Is there an issue using soft water causing my low numbers? I felt that my brewing technique was improved the last two runs, but my numbers just don't show it. Only difference was the water.