Originally Posted by bsteele
Take your reading before adding yeast. If you take it after adding yeast, there's the possibility that you'll drain some of the yeast... but what's a couple yeasties, there's like 18 million billion gazillion more floating around
... or... something like that.
Since oxidation is good at that point, I put back the beer I use for the OG. With a big splash at that
Of course, you have to sanitize your hydrometer. But I hate wasting beer