You did not look under that pot, did you? That is where they were hiding from the rain and snow and frost...whatever. You brought them in. Tiny black ones are easy to get rid of WHEREEVER THEY COME FROM.
Get some baking soda a teaspoon of dry powder and icing suger 1 teaspoon dry powder and mix the two together dry. Use a toothpick or a fork as you only have a tablespoon in total. Now sprinkle it along the wall by grabbing some powder in between your thumb and pointer finger and take a pinch and sprinkle it near the wall corner where the ants were walking as the ants follow the wall along the baseboard. That may mean up on your countertop too. Ants walk that route because they smell where the other ants went. So that is their path.
. The ants you see are the worker ants who do not EAT. But they can taste the sugar as food but cannot taste the baking soda. Why you mix the two together is because the icing sugar is slightly sticky and will stick to a baking soda grain and the ANT being superman can and does pick both of them up and takes it back to the nest to feed the Queen(the only ant that EATS and the only ant that lays eggs, so SHE is the nest. She will pump out 60,000 worker ants. Those ants once they start work, start self digesting so they live for about 2 weeks and then die. Other ants will pick up the dead ant and take it away to the nest as building material. They are gone. That is the way an ant nest works.
The icing sugar is food for the Queen. She also cannot tell that there is baking soda in the sugar and eats that too.
. Ants have a hard shell body. They also have a digestion system like us...acid in the stomach. When baking soda and acid combine....it fizzes. In this case in the stomach of the Queen ant. Hard outer shell ant basically EXPLODES. The Queen is dead.
. There is no replacement Queen.
The Queen gave out directions daily to the worker ants. They got no direction and sort of lose it. The ants disperse and go their separate ways. The worker ants will live for a maximum of 14 days. (the Queen, had she not been poisoned, could live several YEARS)
That is the story with sugar ants. That is what the tiny black ants are. Baking soda or icing sugar is not poisonous to you or the pets or kids. The ants will find it if you put it where they walk and the word gets out to the other ants about the food source.