I would use Terro which is borax in a sugar solution.
https://www.amazon.com/dp/B00MYIS7YW/ref=asc_df_B00MYIS7YW5371011
It really is the best thing, though it takes a while. It's also basically nontoxic for humans and animals, so it's a great fit for you it sounds like.
BTW you can get this cheaper locally than on amazon, most likely.
Terro Liquid Ant Killer Baits( 6 Bait Stations Net Contents 2.2fl.oz/0.36fl.oz) https://www.amazon.com/dp/B00MYIS7YW/ref=cm_sw_r_cp_api_uaqHybWQANNX7
Those are the ready to go baits. You can also buy just the liquid and put it in a bottle cap or something.
something like this would work
https://www.amazon.com/Liquid-Stations-Contents-2-2fl-oz-0-36fl-oz/dp/B00MYIS7YW