Basically a coral wholesaler / coral propagator. The storefront is really just a gigantic greenhouse on his residence. He's been around forever, so he's sort of in the same category as folks like Julian Sprung, Anthony Calfo, etc.
Basically think of it as "The Mother Of All LFS's"
- greenhouse after greenhouse with tank after tank full of stuff to buy.
Problem is as Canadians we can't really legally buy from him (and carry the stuff over the border). But, it's still neat to see. I'm sure that folks probably do buy the occasional thing from him and drive back, but, I've never tried this so do check into it before trying it yourself. Fish, and soft corals are typically not CITES protected so there shouldn't be an issue bringing any of those across, but live rock, stony corals and clams you should technically have a CITES import permit. Like I said though I haven't tried it, there might be others in your area who have though and could advise you better than I could.
Like I said though, if nothing else it's worth going there just to see such a large scale operation. It's jaw dropping and will likely give you tonnes of ideas to try for the hobby. Plus you can get books and dry goods and stuff.