I brewed my first all grain batch this past weekend and everything went pretty smooth except my OG was 1.050 instead of the 1.056 I was expecting.
Would this be a sparging issue? I had calculated a 75% efficiency. I did fly sparging with a home made sparge arm that worked pretty well. I had to adjust the flow a couple times to maintain a flow that ended in 45 minutes with close to 7 gallons collected for a 5 gallon batch.
I boiled off between 1.25 and 1.5 gallons of wort.
If this isn't a sparge efficiency issue what else could it be?