I don't usually have a problem with those little ants, however last year, they were coming into a turkey pen, under the fence. They were after the spilled feed. I put down DE really heavily all along the fence line and it stopped them. I have also been told Nutrisweet will kill ants. Think about that, all you people who drink diet soda. Sprinkle it around the ant hill.
Are you using what they consider food grade DE? My cockroach problem went away after some trapping and I think they must have been rampant from a hatch, but now I have billions of crickets when I put the girls to bed at night. I got the DE at TSC and it shows it as a food supplement for all types of livestock. Is that the one that kills bugs? I saw the pest control one but it said not to use around kids or pets so I figured it wasn't safe for my chickens.