# Travel >> Transportation >> RV

RV: How to Freshen the Fresh Water Tank & Remove Black Scum

Disinfecting the freshwater tanks on an RV can be done easily prior to the first trip of the season. The reason to sanitize the fresh water tank is to disinfect the tank and kill bacteria/black scum that may have grown during off-season storage of the RV.

Even though there maybe a certain odor emanating from the water that resembles rotten eggs, or an unpleasant taste, sometimes there is no taste or smell at all. But if the fresh water tank has not been disinfected in a season, it is best to take precautions to avoid getting seriously ill while on vacation.

Liquid bleach
Gallon bucket
Freshwater hose designed for RV
Plastic funnel
White distilled vinegar

Instructions

- 1
  Empty the freshwater tank completely.
- 2
  Drain your water heater of stale water by removing the drain plug and releasing the pressure valve.
- 3
  Measure a 1/4 cup of bleach per every 15 gallons in your holding tank. Mix 1/4 cup of bleach with 1 gallon of water in the bucket. For example, if your holding tank is 75 gallons, you will need 5 gallons of water mixed with 1 1/4 cups of bleach.
- 4
  Secure the plastic funnel to the freshwater intake opening and pour the bleach mixture into the tank.
- 5
  Attach the freshwater hose to the water supply and fill the rest of the tank with freshwater.
- 6
  Let the mixture sit in the tank for three hours.
- 7
  Open every faucet inside the RV, including the shower, and empty the freshwater tank completely.
- 8
  Fill the freshwater tank again, using the same mixture ratio you used earlier but instead of bleach, use white vinegar to eliminate any chlorine taste left in the tank.
- 9
  Take the RV to a dump station and empty the gray water tank. Run the shower and faucets to allow the freshwater tank to empty again.
- 10
  Once home, use the freshwater hose to refill the fresh water tank for your vacation. The tank is now disinfected and there should be no foul taste or chlorine smell.