Join Date: Sep 2003
Location: San Francisco, CA
It's weird, when I first started DIY, I would get that stuff all the time. Now, however, I never get it. I don't know why as I'm not doing anything differently.
That said, yes, if I wipe it off, it usually goes away. For a time, at least. It may come back, but it's harmless so there's nothing to worry about.
The thing you should worry about is the fact that it's growing on your plants, too. This may mean that your mixture is leaking into your tank. Check your setup to make certain that all connections are good and that the container you're using is big enough for the amount of sugar and yeast you're using.
The fungus is harmless, but you would not want the "yeast wine" getting into your tank.