When you see water rising in the sight gauge on your separator, you know for sure you are separating and removing water.
When the water stops rising in the sight gauge, the water has been removed from your tank.
When you see particulates or sludge in the primary filter bags, you know you are removing contamination from your tank.
When you see the primary filter gauge is not rising with the system running after a filter change, you know the filter is no longer collecting debris and your fuel is clean.
LEARN MORE: What Is Bad Fuel & What Can I Do About It?