"A Handful of Water"

This is an excellent movie.  Here is an abbreviated précis that accompanies the trailer:

"Jürgen Prochnow stars as Konrad, a cantankerous old man still mourning his wife’s death, living alone in a large house with little but a tropical fish tank for company. At the other end of town, 11-year-old Thurba (Milena Pribek) has other problems: the police are at the door and want to deport and resettle her Yemeni family to Bulgaria. But that only works if all the children are there, so the resourceful young girl jumps from the second floor and runs away to seek shelter and food in Konrad’s basement... the unlikely pair strikes up a tender friendship that will change both of their lives forever."

One interesting (and presumably intentional) item is that the model ship on the bottom of Jürgen Prochnow's aquarium appears to be a U-boat.