Kegged my black IPA yesterday, and upon cleaning my hydrometer I noticed there is liquid inside of it, looks like water. It looks almost like condensation which has built up, roughly 2-3 ml of it down in the bulb. I have never dropped it & always babied it (I've had it since my start in 2013) so there is certainly no crack in it...I'm baffled as to how it got in there?? My wife is a biomedical engineer (aka smarter than me) and says you have to have moisture inside of it to begin with in order to have condensation form inside of it...anyone else ever have this happen?