I’ve been diligent about keeping the room clean, not leaving food out, and cleaning up any messes. I also discovered ant chalk. It looks like regular chalk but apparently has some chemical in it that kills ants. I draw it over any ant trails I find then the next day there are no more ants walking on the trail and usually a bunch of dead ants near wherever I put the chalk. There’s just the occasional ant inside now and the situation is manageable.
I’ve gotten some recommendations to use Borax. Mix it with honey or anything sweet then the ants eat this or take it as food back to their nest then all the other ants eat it and it kills them all. Sounds great! But maybe not an approach approved of by buddhists. So I haven’t tried it. That, and it turns out Borax is rather difficult to acquire in Thailand. At home it’s easily found in grocery stores usually next to laundry detergent. But I haven’t seen any in Thailand yet. Apparently some people were adding it to food which then led to Borax being regulated.