Worms can survive under water while ants can't, so how about plugging any holes in the bin and then flooding it for 5 minutes or so? I expect that very ant in the bin will float or drown. Remove any decomposing food that might irritate the worms.

I second suen, to a point. Whenever I see ants I make sure the bin gets doused, as this is intolerable to ants and a matter of indifference to the worms. Whether it's bad enough that flooding is necessary is up to you ;).

I should've posted an update, but what I did was moved the bin to a different location. When I did that a lot of the ants scurried out (luckily they weren't making a nest in there). Then I got a few cups of water and poured them into the bin because I kept reading that ants hate excessive moisture. I didn't plug the holes (I'm just now seeing your suggestion, Seun) so the water drained out. I shredded a bunch of paper and added that to my bin to take care of the excess liquid. Thanks so much for responding, y'all. I was freaking out and felt really bad for my worms.

In my experience, ants will move in whenever the top half (or some less) of the bin is too dry, or if there is too much dry/drying worm

feed in the bin, especially oats or wheat products or corn meal. You can help keep the top moist by covering it with damp shredded paper, damp burlap, soaked leaves, or just by adding a couple extra handfuls of wetted peat, or other wetted moisture holding bedding -- and lighten up a little bit on the worm food.

Dott,

Wicking also seems to be a very effective means of keeping the top bedding moist. Take an old cotton shirt and cut it into a strip per bin. Place one end in a jug of water, and the other end should ideally lay over half or more of the bin's surface area. I try to make the strips like a stingray with an especially long tail.

As long as the jug has water the wick can reach, the other end will remain moist, and anything it directly lays on which has enough air space (like cardboard, will also remain moist.

i've been doing this for a couple weeks now on four bins and a bucket. The bins are definitely drinking, and it has shown. The last time I was there I had no need to water anything. I need more time but am beginning to suspect that the wicking encompasses more volume of the bin as time goes on. So that, by now, everything is uniformly moist and now I top off jugs instead of watering.

The populations are thriving in all bins now, a big difference in a few weeks time. The bucket is daily breakfast for some varmint, yet still it is home to many worms.

All of the worms are gathered under this moist cotton, in all bins but the big blue bin, which I think is large enough that there may be separate colonies which like and hold their turf. This is biased however by the fact that I feed them under the cotton ;). The melon I gave last week is nothing but seeds now, so in the last feeding I loaded them all up with frozen, thawed and finely diced watermelon.

One other thing, my compost pit was built directly to my fifties pamphlet "let an earthworm be your garbage man". It is dead easy and requires no turning, just adding courses of blocks as needed.

Anyway, I was adding a course and had to replace a lower block. When I pulled it out, I saw two red wrigglers feeding, showing that the older compost has cooled and they've moved in. I have my pick of the litter for compostables and I choose their favorites. The pit is near fruit trees which most certainly will benefit. I made a trail of egg shells from the pit through the trees. I want to direct this herd I'm raising, like the end scene to David Lynch's dune, without fighting.

There have been some excellent comments here. I particular like Dott's Idea of wicking.

I have been worm composting on a larger scale for nearly 20 years now and one of the recurring questions I received was the concern of worm bin owners about the invasion of ants into their worm bins. Most ant species are competing with the worms for their food and are not a direct threat to them. Some varieties though like “Army ants, Red fire ant and the “Carpenter ant” are exceptions to this rule. As suggested before one of the best ways to get rid of an ant colony that has infested a worm farm is to flood the bin with water. Depending on the size of your bin pour several liters or up to a gallon of water over the surface of the worm food and worm bedding which will will make the ants extremely uncomfortable and they will as fast as they can try to get out of this wet environment to look for dry pastures. It is important to make sure that there are enough working drainage holes in the bottom of the bin to prevent the worms from drowning. They breath through their skin and can life for extended times suspended in water as long as it contains enough oxygen. So they won't mind a little diving action in their bin at all :-). The flooding should take care of the ant population for now but ant colonies are constantly sending out scouts to search for new food sources. So sooner or later the same or another ant colony might invade your worm farm again if given the chance.

The in my opinion best way to keep ants out of a worm bin for good if it is placed outdoors is prevent them from entering in the first place. I don't like to work with any kinds of poison so we developed worm farms that I called worm farm islands. It’s a fancy description for worm bins that are completely surrounded by water. Similar to many of the old castles in medieval times.It’s really easy and cheap to set up and is virtually foolproof. You just need a container that is at least a little bigger than your worm bin a few bricks and some water. I set one of those worm islands up in less than five minutes and have been running some of them for years. So far there hasn't been an ant invasion in any of them. Ants can't swim. I have published an article with pictures about that subject which should help you to keep your worm herd safe from ants How to protect worms from ants from now on.

All be best to all you worm composting enthusiasts and happy worming.

Kind regards

Stephan