my friend has bugs in his airlock

[ColonelForbin]

they are just floating around dead in the airlock. i told him about a week ago to immediately change the water and replace it with vodka. he never did and now more bugs showed up. this happened to me once in the past and i was wondering what causes it and if it is harmful to your beer. i remember my beer with this problem still tasted fine but i fixed the problem immediately.

 

[Nugent]

I'll bet they're fruit flies. As long as they don't get in the beer, things will be fine. I'd replace the airlock, and use vodka or a sanitizer.

To avoid them to begin with, put a small bowl of apple cider or red wine vinegar mixed with a few drops of dish soap mixed into it. They'll be more attracted to it and drown in the solution.