The German word for river is Fluss. Fluss is male, therefore it has the article der. Der Fluss.
Fluss - 2012 is rated/received certificates of: Sweden:7
The cast of Am Fluss - 2012 includes: Marten Krebs as Nick
The cast of Fluss - 2012 includes: Max de Mora as Child
Stadt Land Fluss - 2011 is rated/received certificates of: Germany:o.Al. (f)
river = Fluss
Der Fluss war einst ein Mensch - 2011 is rated/received certificates of: Germany:6 (f)
The cast of Im Fluss des Lebens - 2012 includes: Ana Epulef Luis Infanti Lili Schindele Doug Tompkins
Inge Kramer has written: 'Menschen am Fluss'
The cast of Der Fluss war einst ein Mensch - 2011 includes: Obusentswe Dreamar Manyim Alexander Fehling Sariqo Sakega
Martin Fluss is probably a very nice person to his friends, coworkers, and family. There is no website that says that he is a bad person and has never been mentioned on any social network as being a mean person.
Take it to a gunsmith.