I'm in the northeast and don't know what rover ants are. Are these small ants? If so, then they are not going to the exterior as larger ants do, so the Termidor won't affect them. I suspect that they are living under slabs, in wall/ceiling voids. For the smaller ants we use Gourmet ant gel and Abathor based baits in conjunction with non-repellent sprays such as Phantom, Premise. We've had luck with Temprid, although it is a repellent.