I know nothing about the hydrometer
If you want to know what's going on with your beer, then that's what you use. The only way to truly know what is going on in your fermenter is with
your hydrometer. Like I said here in my blog, which I encourage you to read,
Think evaluation before action you sure as HELL wouldn't want a doctor to start cutting on you unless he used the proper diagnostic instuments like x-rays first, right? You wouldn't want him to just take a look in your eyes briefly and say "I'm cutting into your chest first thing in the morning." You would want them to use the right
diagnostic tools before the slice and dice, right? You'd cry malpractice, I would hope, if they didn't say they were sending you for an MRI and other things before going in....
You don't just throw more yeast at the situation, you don't even know if oyu have a problem.
Thinking about "doing anything" like repitching, or bottling, or racking, without first taking a hydrometer reading is tantamount to the doctor deciding to cut you open without running any diagnostic tests....Taking one look at you and saying, "Yeah I'm going in." You would really want the doctor to use all means to properly diagnose what's going on?
[ame=http://www.youtube.com/watch?v=xtQt7HiObuU&feature=relmfu]Hydrometer - Brewing Beginner Series - YouTube[/ame]