I keep mine in a very fine powder so that I can always sift the worms out from the bedding. Then I put the pile of worms in a tub that has holes drilled in it that are just big enough for the live worms to crawl through (and keep it above the new tub/bedding you want them to crawl into.) The majority of the dead worms are left behind and the live worms are now in their tub. Then again, if you don't keep thousands and/or are not lazy (unlike me) you can just pick out the live ones from the dead ones. I use the drilled tub method to help separate out different sized bugs too (different sized holes to separate smaller bugs from bigger bugs.)