RV Fresh Water Tank

How To Sanitize RV Fresh Water Tank Within 6 Easy Steps

Updated October 2, 2022

- By Tim Harris

If you want to enjoy your RV adventure or camping to the fullest, you should ensure the proper working condition of your RV’s freshwater system. And that’s why you need to know how to sanitize the freshwater tank on an RV.

At every six-month interval, you should clean your RV’s fresh water tank. If you don’t clean the freshwater system, you may suffer from an illness on your trip. Thus like your RV’s any other part, you should also frequently clean its freshwater system.

Regularly cleaning and sanitizing your RV’s freshwater tank will supply odor and germ-free fresh water. But if you don’t sanitize the tank, bacteria and mold can grow in the tank from the grime or sediments to contaminated water. Thus, cleaning and sanitizing the freshwater tank is crucial for your health and safety.

Supplies Require to Sanitize the RV Fresh Water Tank

The following materials require you to sanitize and clean your RV freshwater tank. Check the list below:

  • 1-gallon pitcher
  • Safe hose for drinking water
  • Clorox disinfecting bleach
  • Water transfer pump (Self Priming)
  • Deodorizer and system cleaner for freshwater
  • Measuring cup
  • Funnel


How to Sanitize the Fresh Water Tank On An RV

Reading the topic of sanitizing the freshwater tank, you may think it’s a hassle, but it’s not. You can complete your RV fresh water tank’s sanitization following the simple steps below.

Step 1: Turn Off the Hot Water Heater

At first, turn off your RV’s hot water heater and then take prepare for freshwater tank sanitization. Your water heater can damage during the sanitization process if you overlook this easy step. Start the sanitization process later. First, turn off the heater and ensure that the water cools down inside.

Step 2: Empty Your RV’s Fresh Water Tank

To correctly clean the freshwater system in your RV, you have to empty the tank. First, clear the tank’s previously stored water. However, before draining the tank’s water, ensure that the freshwater connection is turned off. Next, empty the water tank by opening the RV’s outside valve.

Ensure no water is sitting in your freshwater tank’s pipe and turn on all the faucets. Ensure your RV tank is cleared correctly by using the water pump.

Step 3: Prepare the Water and Bleach Combination

How much amount of bleach is required for cleaning the RV fresh water tank is essential to know. Calculating the exact amount is necessary because excessive use of bleach can damage the pipe. Too little bleach will not thoroughly sanitize your RV’s freshwater tank. Again, the RV tank, tube, and seal can damage if you use too much bleach.

For your RV’s water tank sanitization, use fresh water in 8 gallons and 1 ounce of bleach. So, if your freshwater tank’s size is 60-gallon, for sanitizing it, you will require 7.5 ounces. Don’t pour the bleach directly into the freshwater tank.

First, calculate the bleach’s appropriate amount and then take a gallon of water to dilute it to the water. And after mixing it correctly, add the mixed water to the tank.

Step 4: Fill the RV’s Fresh Water Tank

Ultimately add the bleach water mixing in your RV freshwater tank. And then use the potable freshwater to thoroughly fill your RV’s water tank. Ensure that the bleach perfectly reaches the tank’s every part. Next, open each shower and faucet’s cold side until you don’t get the bleach smell from each.

At a time, open your RV tank’s each fixture. You should run all the taps as long as you get the chlorine smell. Then turn all the taps off and let the bleach water sanitize your RV’s water tank.

Step 5: Give Time to Sit the Bleach Water

To make your RV’s entire freshwater system clean and sanitize, the bleach water will require some time. The well-diluted bleach water takes at least 15 minutes to run through the water system. After that, the bleached water will clean all the germs and contaminants.

The solution ideally requires sitting in your freshwater tank to properly kill all the harmful germs, odors, and bacteria. By sitting for 15 minutes, the solution will rinse away all the contaminations and other mineral build-ups.

If your freshwater system has horrible contamination, you require at least 4 hours to complete the sanitization perfectly. So make sure the solutions sit in the tank for at least four 4 hours. You can keep the solution for 12 hours in your RV’s tank to get the best result. As it requires enormous time thus, the more convenient time is to fill the tank at night and drain it in the following early morning.

Overnight the solution will get enough time to sit in the system. Keeping the solution all night is especially important while you are staying in your RV. After completing the sanitization process, the tank will be ready to use on the following day.

Step 6: Empty Your RV’s Fresh Water Tanks and Flush It

Once the bleach water perfectly sits in your RV’s freshwater system, now it’s time to flush the tank. Empty the tank by opening all faucets together. Then use potable freshwater to refill the tank. Make sure that, ideally, the water in your system circulates through the tank. Use the water pump to ensure the water’s proper circulation.
As long as you are not getting the chlorine smell, you have to circulate the water in the tank. Thus filling and emptying your RV tank may require several rounds to clean it perfectly. However, the best time is when you freshly sanitize your RV tank to change the water filters. Then, turn on the water heater again. And for your next trip, the freshwater system in your RV is perfectly ready.


How Often and When to Sanitize Your RV’s Fresh Water Tank

If you want to consume healthy and clean water while you are on a trip, you should regularly and adequately sanitize the freshwater system in your RV. When you use your RV tank’s water, it becomes lowers. So quickly, the moisture and mineral build up in the waters above space. And this space has become the perfect breeding ground for bacteria, mildew, mold, and other contaminants.

Using a powerful sanitizer regularly to sanitize and clean your RV’s entire water system is the only solution to this issue. However, you should sanitize the freshwater tank in your RV at the following times:

  • If you purchase a new or used RV, you should first clean and sanitize its tank.
  • For full-time RVers, the recommended time for sanitizing their RV is at every six months at least.
  • When you start to get a stale odor from your RV’s tank water.
  • Usually when after long wintertime, you take out your RV from storage.
  • When you fill the drinking water from a campground where the water is dirty or not healthy to drink.
  • The whole water line gets contaminated because of dirt in the drinking water.
  • If you find slime or algae in your RV water tank.
  • Your RV is not in use or sitting around for more than two weeks, and the water in your RV’s freshwater tank remains unused.


How Long Can the Fresh Water Keep in The RV Tank?

For up to two weeks at best, you can keep the fresh water in the tank, and it remains safe. But you should not use the water that is in your RV tank for more than two weeks. Because after two weeks, the odor, bad taste, and minerals start to build up in the tank. Don’t think that you can use the water for more than two weeks by using the RV water tank.
The mold, mildew, bacterial and fungal spores find their way and contaminate the drinking water in your RV’s water tank even after using the water filter. Try to refresh and clean your RV’s freshwater tank every two weeks. You can use your mobile device to set the reminder or use various RV maintenance and applications to give you the two-week reminder.

The Easiest Way to Keep the Fresh Water Tank Clean
You can clean your RV’s fresh water tank in many easy ways. You can add a preventive maintenance checklist for your RV to maintain the tank sanitizing schedule for six months. Also, before filling the water in your RV’s fresh water tank, make sure that the water’s purity level is excellent.
Seasonal RVers or full-time RVers can sanitize the fresh water tank in their RV every four-month rotation. However, full-time and seasonal RVers should sanitize their water tank more frequently because they hold and use the water in the tank more often.



So, after reading the above informative guide, now you know how to sanitize the freshwater tank on an RV? Depending on how frequently the RVers use their RV, they should sanitize and clean their RV’s tank. To sanitize and clean your RV’s freshwater tank, you can follow different treatment options. However, sanitize your RV’s tank properly and drink fresh water and reduce the chance of getting weak during your trip.

Only use the potable water to fill the freshwater tank in your RV. Also, make sure that the drinking water’s source is clean enough; otherwise, the whole water in the tank will contaminate. And you have to clean and sanitize it more frequently. So regularly sanitize your RV, keep out the contaminations and reduce the bacteria and mineral build-up with your RV’s freshwater tank.

Tim Harris

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