Soak the pearl barley for at least 2 hours or overnight. Drain and set aside. Also soak the pork bones in cold water for 1-2 hours to purge them of impurities, changing the water once halfway through.
Rinse the pork bones clean, using your hands to scrub them of any impurities and bone spurs. Transfer to a deep stock pot with just enough water to submerge them. Bring to a boil, and boil for 1 minute. Remove from the heat, rinse the pork bones clean, discard the water, and rinse the soup pot clean.
Add the pork bones back to the stock pot, along with soaked barley, dates, 8 cups water and the ginger slices. Set over high heat, and bring to a boil. Once boiling, immediately turn the heat down to medium low, cover, and simmer for 2 hours.
While the soup is simmering, slice the bitter melon in half lengthwise. Use a spoon to scoop out the seeds and scrape away all of the white pith, which can be particularly bitter. Cut each half into large chunks. Set aside.
After 2 hours of simmering, skim the fat off the surface of the soup. Add the bitter melon, cover, and simmer for another 30 minutes. Add salt to taste before serving (you can also add MSG for extra oomph if desired—this is completely optional!). Serve with light soy sauce to dip the tender pork ribs into.