No. the conditions in the two bins are, in some way, different to the point the wormies flee the un-vented one. (Moisture?)

.......BUT........"wierd" ain't the word for it.

I have no vent holes in the top but I dont keep it closed I leave a very slight crack. I dont want to leave any more that that as it seems it dries out a bit. But I do have 1/4" screening in the bottom of each of those tiered bins. Works well for me worms stay in the bin.

As much as it pains me to post on houzz, since it is just like bad, your predicament needs answering. By "multiple escape attempts by the dozens?" do you mean the worms are enjoying the moist air and slimy walls of the covered bin? Or have they actually crawled out of nirvana and into the cold, harsh, oxygen rich air of the outside? In moist conditions worms are supposed to "go west young man". Not having the cover off provides exactly the conditions worms are supposed to move around in. Worms are smart. They know from more than two years what to do to survive. Vermicomposter confusion of what they think proper worm activity is does not stop worms from... being great worms.

That very slight air addition Steve has for the worms removes moisture that encourages the crawl. We need to understand worms and work with them not create prisons to keep them in poor situations. If the environment we give them is great they will not want to leave even if nothing stops them. Covers on bins do not keep worms in. Covers keep moisture in which makes the perfect environment for worms to crawl all around. In about two years my post will not be needed. A computer pretending to be a poster will be using my exact words to generate clicks to charge advertisers. This will be true even for sites catering to organic, local, vegan, stuff. This is all just an information gathering, harvesting thing. Get your information now. Before all your worms crawl away. :-)

Thanks much, all 3 posts great info. I have made multiple attempts over last few days to post but I have been waltzed around by the new regime. Finally I tried to sign up with new name and they said already signed in. Over my head. Maybe they just gave me a break because today is Sunday.

I kind of knew that moisture was the problem but my spray bottle broke last yr and I kept forgetting to buy a new one. I don't like to put water in the bin without a sprayer once established. Never had leachate on bottom and don't want any. Your postings incentivized me to get a new spray bottle and take care of business, so thanks. For the most part worms have settled along the sides and top of rim right under the cover. I flick them back in every few days before they watch one of those old J Cagney movies and go over the wall. I do leave a temperature gage in the bin which also serves as a tv.

The bin in question was moist but maybe not where you could ring a drop of water. The sides were wet and maybe that's why the worms congregated there. My other bin is like mud but the sides are dry like sandpaper. Maybe that's what keeps them settled on the bottom. I would think that the thick mud would be almost suffocating but that just goes to show you that my ex-wife was wrong about me. I am not a worm and don't think like one. I have always tried to avoid such wet conditions but I may be more tolerant now and just let it dry somewhat before harvest.

OK here's the kicker. The dry bin with so many worms hanging out along the wall looks more populated and an inch or so more compost than my other bin. Maybe I put more worms and stuff in there to begin with, don't know. Anyway, I thought this might be good info for the newbies but they are probably more confused than ever. I will let you know how I make out after a couple weeks of water works if the new regime doesn't hassle me on sign in.

"I do leave a temperature gage in the bin which also serves as a tv." Like.

"I would think that the thick mud would be almost suffocating but that just goes to show you that my ex-wife was wrong about me." Like.

"I am not a worm and don't think like one." That takes many hours of sitting and looking at the bin. Even looking at the bin with the cover on helps.

"Anyway, I thought this might be good info for the newbies but they are probably more confused than ever." If they are not confused when they get here they probably are when they leave. We do try.