My brother uses a bait(powder )that the ants take back into the nest and transfer to the other ants killing the whole nest...(don't ask me for the brand name)...I use a spray that looks like milk/malathion...just don't use it in any kind of wind and use a heavy spray not a mist(pump sprayer)just follow the directions on the jug.later...
Terro- This is mostly for those pesky little sugar ants but I havent found an ant it wont kill!! Its a bottle of liquid that you place on small paper pieces, ants eat it take it back to their nests and share to kill!!!!! Sometimes takes about 4 days but theyll b gone 4 good...
If you don't have a dog or cat or kid that will get into it, take two parts Borax to one part sugar and sprinkle in where ever the ants are. The borax powder sticks to the sugar, the ants eat the sugar and die. The borax also sticks to the ants, they carry it home and kill their any families.