I'm running water out to the barn come spring. We have a well. Barn is about 125 ft away. Should I run 1" pex because of the distance, or stick with 3/4"?
I assume you're running it underground? If so you would better off using High Density Polyethylene, it's typically what is used for water services. 3/4" should suffice. I see you're in Michigan, so bury it deep. Check your local codes and see what is recommended.