I sanitized my last trailer when I bought it and did not again for the 8 years I owned it. Drank the water from the tank also however I used it every winter. My present trailer was sanitized once also. I use city water so that will keep it sanitized.
2011 F-350 CC Lariat 4X4 Dually Diesel
2012 Big Country 3450TS 5th Wheel