I use Harris Boric Acid Roach Powder with Lure. Ordered from Amazon. Doesn't say it's for ants and company says the lure does not attract them. I added a bit of powdered sugar to the container.

BTW-- On sale right now on Amazon with same-day delivery in my area!

https://www.amazon.com/Harris-Boric-Silverfish-Killer-Powder/dp/B0026MD0G6

NOTE: this is mildly poisonous to humans and pets so for outdoor use or somewhere kids and pets can't get it! (Like under the fridge.)

A good friend of mine who works for a pest control company once told me “If people knew about boric acid we’d be out of business.”

Not to be confused with Borax, boric acid is a white powder that costs $7 for a lifetime supply (ex: https://www.amazon.com/dp/B0026MD0G6) You lightly dust it in corners and anywhere cockroaches are likely to hide.

It won’t stop them coming through pipes if that’s indeed where they’re coming from, but it works better than anything I’ve ever used. Takes about 2 weeks but it wipes them out. Then you can just leave the hidden away spots dusted and it’ll continue to work for years.