Sanitizing fresh water system, from Bigfoot
Put 1/4 cup of household bleach in a gallon of water (amount for 15 gallon tank, increase or decrease as needed). Pour that into the fresh water tank and then fill the tank completely with fresh water. Turn on the pump and run each faucet until you detect the smell of chlorine. Allow 3-4 hours of contact time. Then drain and flush until you get rid of the chlorine.
If I remember correctly, Casita
recommends Sodium bicarbonate to get rid of chlorine or other odors. My Casita
manual went with the trailer.