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RV maintenance is the key to a smooth camping experience. When sanitizing RV tanks, one question many people ask is how long to leave bleach in RV water tanks.

About 11.9 million Americans owned an RV in 2021 and most of them planned to take it out on their next trip. As such, water tank sanitization should be one of their chief concerns.

There is no exact quantity or time you need to leave the bleach in to sanitize the water tank. On average, you should place one cup of bleach for 60 gallons of water. The bleach can sit in the tank from anywhere between four hours to 12 hours to eliminate bacteria and make it safe to drink water.

In this guide, we will learn how much bleach to add to a water tank, how long to leave it in, and whether bleach causes damage to the water tank. We will also write about the proper way to sanitize the water tank in your RV.

As a camper myself, I always sanitize the water tank with bleach or another cleaning solution before I take my family out on the RV. This is what I do to clean the tank.



How Long Should You Let Bleach Sit in Your RV’s Water Tank?

As an owner of an RV, I know that bleach is an excellent water tank sanitizer. People who are using it to sanitize their water tanks for the first time might be wondering how long the bleach needs to stay in the water tank to get rid of pathogens.

It is a good idea to let the bleach solutions sit in the water tank for at least four hours. In fact, you can even leave the solution in the water tank overnight.

This can be quite a good idea if you think that your water tank requires deep cleaning.

How Much Bleach Should Be Used to Clean Your Water Tank?

There are various opinions when it comes to the amount of bleach that should be used to clean the water tank. None of these opinions is wrong.

According to the San Antonio government, you should place about 1/4th cup of household bleach to disinfect a water tank of 15-gallon capacity.

So if your RV has a 20-gallon fresh water tank, you need slightly more than 1/4th cup of bleach.

You will adjust the quantity depending on the size of your RV water tank. The math is very simple.

How to Clean Your RV Fresh Water Tank with Bleach?

It might take a few hours to sanitize your RV tank, but it is quite a simple solution. All you need is bleach and water. You can also use other disinfectants like vinegar or baking soda in water but bleach is by far the most effective and reliable way.

Step # 1: The first step is to drain out any water from out of the fresh water tank and system. This should include not just the water reservoir but also the water heater. You can do this by looking for all the water valves and opening them. There is typically a small plug that you need to pull out to drain the water.

Step # 2: While the water is draining, use the time to create your bleach solution. Find out the total size of your water tank system and add about 1/4th cup for every 15 gallons.

Step # 3: Fill up the entirety of your water tank. You need to make sure that all the pipes and tanks in your water system are sanitized so turn on all the faucets in your RV so that the bleach can make its way through the entire system. Once the water starts flowing from the faucet, turn them off again.

Step # 4: Now that the hard part is done, you need to let the solutions sit in the water tank. Some people think that just allowing the water to run through the system will get the job done. However, it takes more than a few minutes for the bleach to effectively get rid of pathogens, so it is important that you let the solution sit for at least four hours.

Step # 5: Once the hours have passed, you can flush out all the diluted bleach solution. Open all the faucets so that the bleach solution can drain out. Then fill your tank with fresh and clean water and let it flush out of the system until the bleach smell has gone away, taking the corrosive chemicals with it.

You can now fill the water tank again and enjoy clean water safe for drinking.

Will Leaving the Bleach for Long Damage the Water Tank?

You can safely allow the bleach to sit in your water tank for 12 hours or even more and it will not damage the plastic of the water tank, the water pump, or the pipelines. Even if you add a stronger solution, it will not damage your tank.

That is because the bleach you added to the tank is diluted by a much larger quantity of water. Although it will kill all the harmful pathogens in the tank, it will not harm the tank itself.

You should also keep in mind that bleach itself comes in plastic bottles and sits on your home’s shelf for several months or even years without damaging the container that it is in. Neither does the bleach harm your flooring nor the washing machine.

Hence, it is proof that keeping the bleach solution in your tank overlong will not damage its walls or the rest of the water system.

Is It Possible to Use Too Little Bleach in Your Water Tank?

Interestingly, even placing a smaller amount of bleach in the water is enough to get the job done right. The whole point of cleaning your fresh water tank is to ensure your water remains safe from the pathogens in the tank. It is almost impossible to kill 100% of the living organisms in your tank. However, even a small amount of bleach will kill enough bacteria so that you won’t get sick.

In fact, some people even add a tablespoon of bleach to their water tank when filling it. This tiny amount of bleach is safe for drinking.

If you think that your tank is heavily polluted, then it is a good idea to use more quantities of bleach.

What If You Have Too Much Algae or Pathogen in Your Water Tank?

If your tank has accumulated algae or if you suspect it is quite filthy, you need to do a more comprehensive job of cleaning it manually with a scrub and soap and water. It is also possible to drive your RV to a dealership and ask them to place another water tank in it.

Most of the time, your water tank will easily last you for four to five years at least.

How Do You Know If Your Tank Has Been Cleaned Well by the Bleach?

A good way to find out whether your tank is clean is to fill a glass of water and hold it up to the light to see if there are any particles in it. If the color of the water looks off or hazy, it might be time to sanitize your tank. However, if your water looks, smells, and tastes fresh, then it is clean and safe for drinking.

Is It Important to Sanitize Your Water Tank With Bleach?

Keeping your water tank clean and sanitized is important for your health. Although the process will take some time and effort on your part, the cost is negligible and the benefits are worth it.

Stale and stagnant water can lead to all types of hazards. Your tank can develop bacteria, algae, mold, or slime and may develop a funky smell. It is a good idea to clean out your tank with bleach every three to six months or depending on how often you use your camper.