I actually have some of my racks that have no males in them. I also have racks that every other tub is a male. I don't know that organizing a rack one way is any better, as I have males across the room from a female will start cruising the tank. I think the pheromones can attract a male from great distances (probably part of how breeding actually occurs in the wild). I can't see any complications, other than your male possibly going on a hunger strike due to his desire to breed.