How long can 500g ink calligraphy be used?

It depends on how big your handwriting is and how often you write it. Pour less ink every time you use it When the ink is used up and water is added, it will not be easy to use. I can save some money by using the ancient oil smoke ink of the Asking Heart Hall, because it is not smelly and has no dregs, and it will still be black after adding water the next day.