For separating, look into what are variously called 'potting mix sieves', 'panning sieves' or 'classifier screens'. For sifting out adult worms, 10 holes/inch works well. Twenty holes/inch works ok for getting the frass out of mini mealies (I use a lot of these for hatchling geckos) but a lot of the oat bran I use for food stays with the worms, so feeding only as much as the worms will eat by the time they'll need to be sifted out is important.
Temporarily putting the worms into a container that is taller rather than wider makes the worms congregate on the surface which can make it easier to simply pull some out. I typically just prop the container (I keep small batches of a couple thousand worms in Kritter Keepers in a fridge) up on end and that's enough to do it.
FWIW, I'm not breeding them but just separating fairly uniformly sized worms from bedding and carrot pieces -- I buy sized worms, as I used 105,000 mealworms in the last six months of 2021 (I just checked my records -- holy cow).
Reply With Quote