I am using an open air rubber maid tote (I don't have a lid for it) with holes drilled in the sides and bottom. If I overwater a little bit water drains through the holes, but some pools in the corners and keeps it too wet. The top of my heap stays dry, an inch down it gets moist. I would guess you'd have success as long as you were very careful with your water.

last time i tried this same thing happened as you but one of my worms escaped somehow i just don't want that to happen. i am going to put a burlap layer ontop maybe this will help keep them in and also water retention

Leave a small watt light on over the bin at night for the first few weeks. Let em get settled in.

Celbrise, I compost in a rubbermaid tub and the thing is a water sink; see my recent posts about the terrible smell. I drilled has about 8 rows of holes near the bottom on all sides plus the lid and it still stays *wet*. I fear your cooler would be even worse. Also, do you know what the metal lining is? I believe worms don't like zinc and you probably don't want metal leaching into your compost either.

You'll get fungus gnats/fruit flies/random flying bugs if you put any fruit or veggies in the bin and don't cover them carefully. The eggs are generally present on the peel. (Harmless to people!)

the metal is galvanized metal so it does contain zinc. however it is a really thing metal sheeting. i just added some worms in today they really don't seem to mind it. i also drilled in holes at the top so i could close the bin again they don't seem to mind they are not trying to run away which i feared hopefully they don't overnight

Mosquito netting held over the top with a bungie cord works well. If in a lit area means worms won't work the surface (a sheet of paper on top of the food solves that) but it's nice to be able to look in without moving the lid.

Freezing kills the eggs btw, but with open vents you won't be able to stop then getting in. I never could with my RM bin, but with a Worm Inn and the zipper lid I've been fly free for two years (indoor system).

i drilled some holes into the cooler and left it open for the first night im glad to say the worms are still in the bin. didn't see any trying to escape or out of the bin the bedding must be good. i thnk it is better because the person i bought the worm gave me some bedding and his was extremely wet and also had maggots in it. mine is just moist no maggots