put semolina,polenta or couscous in a shallow dish,i used a coffee jar lid,and nearly filled it,within a few days all the red ants had gone,if the dish becomes empty,top it up,i would think the little devils only come out when is dry and sunny,if your come out in the wet,put a shelter over it like a ice cream tub with notches around the rim,like when making slug traps,this definately works,look it up on the search,top of page.