I just got a phone call a couple of days ago from a friend of mine that is having the same problem from gnats. Last summer I couldn't go out on my deck without seeing hundreds of gnats flying around everywhere, it's so strange. Anyway.....one thing I know there is no sense in trying to use something to swat them with since they are so small. When they are in my house I use hairspray, the cheaper the brand the better. Mixing White Vinegar with water in a mister also helps. Try to avoid buying fruit that lays out on your counter, like bananas.