Do all the frames in each hive body need to have the same frame spacing for the mites to fall through to the screen bottom? I have dusted my hives twice in the past 2 weeks. I am not seeing very many mites fall. I did not do any pretreatment mite counts so maybe there aren't many normally falling. My hives are all in mediums, and the lower one to two bodies have no bees just stored pollen and empty combs. Some of the bodies have ten frames and some have nine frames. Do I need to reorganize these hives to have all the frames line up vertically and take off the empty combs beneath the cluster so the bees are right over the screened floor?