There are a few stores in Duluth the area. One is "World Of Fish" off of Hwy 53 up in hermantown and there is one across the bridge in Superior "Superior Aquarium" It's walmart if I remember right.
I think Jim's up in Hibbing grabing fraghs for everyone . Check out reef central - Greater Minnesota reef society. I believe he's at Wizdarus house this afternoon and then heading back because he has surgey tomorrow.
Steve gives the best directions hope you can locate them remember were at the end of the world for LFS. To bad I'm not going to be around to have a beer or two and show you my tanks, surgery in the morning.