Lars og Lars S09E01 - Vanvittig vekst på ørret i Groruddalen

Alna is Oslo's longest river. From Lillomarka it flows through Norway's most industrial and populated area. Previously, trout were only found in the upper reaches. This spring, Lars and Arin caught and analyzed trout all the way down to where the Alna disappears underground in Gamlebyen. In the gray-brown river, the fish that survive have an incredible growth rate.