Following the death of his father in 1798, his merchant business went bankrupt. Krohn and his brother Wollert subsequently started the company Konow & Co., which was engaged in fish exports and grain imports. Konow was an alternate member of the Storting 1815–16, 1818 and 1821 and permanent representative in 1824. His brother Wollert died in 1839 after which August continued the company, under the name of Aug. Konow & Sønner.