The last couple of months have seen an invasion of ants in my office building. They are mostly a minor nuisance except that they keep getting into my opened bottled water where they collect on the surface of the water and either drown or invite their buddies in for a swim.
I've tried putting the bottle (1/2 gal) in all sorts of hard-to-reach places, but given a couple of days, the ants always find it. Once opened, there is no way to close it up air tight again. It has a plastic spout that fits over the opening and they seem to be looking for the moisture. I've begun filtering my water through a cloth when I want a drink, but this is really getting annoying.
My question is there some non-toxic, non-smelly substance I could apply around the base of my water bottle that would repel the ants once and for all? This is inside my office so chalk and insecticide are not an option. Any other ideas are more than welcome!