Aloha Oxygen,
I don't know the answer to that one. When Chunyi started to first teach about them, he had people pull out the floating ones, as the quality of seeds coming into the states were low.
Now he doesn't have people remove the floaters because the quality is generally really good.
Caveat: you get what you pay for. I'd purchase them at a place I'd trust the quality of the produce/product, but that's me.
Much Love, Shawn
