Get a cup with a cover that has a straw hole. Put half a banana inside with the peel still on. Put the cover on and make sure the straw hole is open slightly, just lightly press the tip of your pinky in it. The gnats will get in but not out. You can catch a ton this way in only half a day. This will be the quickest way I know of to get rid of 70% or so of them. Your traps and spray should take care of the rest.