Sounds like you need to change the size of the supers as well. Hope it works. Mason bees are an alternative, but it sounds like they are not a full season pollinator.
You know, when these collapse stories came out, the first thing I thought about was the fact that these mega-keepers put these hives in 18 wheel trucks and ship them from one coast to the other, and that can’t be good. Intermingling that many bees, countrywide in the span of a season is not good for their immune systems. They weren’t made for that kind of assault.
“Mason bees are an alternative, but it sounds like they are not a full season pollinator.”
That depends on where you are located and how low the winter temps dip. Every winter I purposely do not cut all of my lavender and rosemary flowers. During mild winters I find Mason bees on them Dec, Jan, and Feb. This past winter I had bees out and about the entire time. The payoff - my biggest crop of peaches ever.