Don't know about Costa Rican ants, but they don't like mint or lemongrass. I use a non-toxic spray.... either Victors, EcoSmart or EcoLogic brands. It kills them on contact, and the residue of the spray wiped on counters and doorways repels them.
Apparently they have Army Ants, some people let them come through once a year, they go through and clean everything out, but go out for the day, as there are hundreds of them.
I would like to know how to get rid those pesty little sink/drain flies. I've tried baking soda and vinegar, drain cleaners and put plastic over the drains.
Try Terra available at big box hardware stores - HD, Lowes and Ace. Comes in various selections and it works.
Don't know about Costa Rican ants, but they don't like mint or lemongrass. I use a non-toxic spray.... either Victors, EcoSmart or EcoLogic brands. It kills them on contact, and the residue of the spray wiped on counters and doorways repels them.
Apparently they have Army Ants, some people let them come through once a year, they go through and clean everything out, but go out for the day, as there are hundreds of them.
https://www.domyown.com/how-to-get-rid-of-ants-a-462.html
Boric acid in their path. They drag it back to the nest and it kills them.
How about a bait trap with sugar and borax? https://www.hometalk.com/diy/outdoor/pest-repeller/quick-dyi-sweet-bait-to-treat-and-get-rid-of-your-ants-18515410
How to Get Rid of Ants With Borax & Sugar