# Travel >> Transportation >> RV

How to Sterilize a Fresh Water Tank

An RV uses a holding tank to isolate the fresh water from the grey and black water. Over time the fresh water tank accumulates mildew and mold. This is caused by air getting into the tank and lines, allowing bacteria to grow. For health reasons, the fresh water tank should be sterilized and cleaned before your camping seasons begins, especially if the tank has been sitting in storage. To sterilize the tank, the faucets need to be functioning in the RV.

Bleach
Funnel
Water hose and connection

Instructions

- 1
  Drain the fresh water tank completely. Make sure the electrical connection is on.
- 2
  Pour one cup of bleach into the fresh water tank along with one gallon of water using the funnel. The funnel and the bleach-water combo will make sure the bleach gets into the tank valves and hose. Remove the funnel after pouring in the bleach-water.
- 3
  Push the hose into the tank and fill with fresh water until full.
- 4
  Turn the RV water pump on and go through the rig opening every faucet, including the shower. Let the bleach water circulate fully through the system.
- 5
  Turn the faucets off when the bleach can be smelled in the RV cabin. Let the bleach water sit in the tank for four hours.
- 6
  After at least four hours, turn the faucets back on and let the tank drain completely.
- 7
  Fill the fresh water tank with fresh water until full.