I was having the worst fruit fly problem the other week. It took me days to figure out what there were feeding on. I have a plastic tub with latching lid that I was keeping my stout in while it bottle conditioned. Hadn't checked on them in some time and a bottle exploded. You wouldn't believe how bad it was. Moral of the story: using plastic tubs to minimize bottle bomb casualties is a good idea, but check it every now an then. I also learned a new trick to catch / kill fruit flys. I had been doing the inverted bottle trick previously, but in this case the fruit flys were reproducing faster than I could trap them. What worked best: small shallow dishes with a drop of dish soap, a touch of water, and cider or red wine vinegar. They can't resist it, and fall right in. Hope someone learns from my mistakes.
