I have seen some beeks using toothbrushes to scrub the back of bees as they enter the hive. Some have suggested using fingernail brushes for this purpose.
I plan to build a Varroa Mitigation Entrance using 2 fingernail brushes arranged facing each other so that it will scrub both the back and belly of the bees as it goes into or comes out of the hive. It will be 2 brushes facing each other with a small gap in the middle.
The brushes are about 7cm long, 3.5cm wide and about 1.7cm in thickness from the brush frame to the tip of the brush bristles. I will then arrange them face to face with a middle gap of 5mm. I will then glue them onto a slot onto a shim arrangement similar to an Imirie shim. The shim will be approx. 5cm thick. This shim can be placed in-between hive boxes to act as an additional top or middle entrance.
My question is, what is the proper middle gap that would work for this arrangement? I know that Queen Excluders have a gap of 4.1-4.4mm. This allow workers to pass and blocks queens and drones.
In your opinion, what should be the proper gap for such a brush arrangement. Is 5mm sufficient for allowing the bees to walk in and out without hurting them too much? If the gap is too wide, it may not brush off the varroa mites. If it is too narrow, it might hurt the bees or maybe screen off its pollen payload like a pollen trap. Is 5mm a good gap distance to allow the bees a comfortable entrance while brushing off the varroa mites without brushing off the pollen load? Once the mites are brushed off, they will fall harmlessly to the ground where hopefully, they will be eaten by chickens. LOL....
What is your opinion?