Watch the video for a quick and easy fruit fly trap that you can make with the items you already have in your bar. Keep a trap close to the fruit trays and they should keep away the majority of those little pests.

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Getting rid of the fruit flies does pose an interesting problem. They are not that easy to kill. Freezing is not recommended as many will come back to life after they thaw out. Microwaving them works but keep an eye on them - it'll only take seconds.
If all that fails, its back to the chickens....