My initial reading was around 1.058 and after 4 days I popped the fermenter and it was 1.020. So I'm pretty happy with that. My question is this, since I just took a close look at the other measurements on my hydrometer and noticed one column with percentages from 0 to to 20 and "Potential Alochol By Volume". So what does that mean exactly? There's also a column that's called "Balling" with numbers from 0-35.