How Long can you keep Water In your RV Tank?


Even if you're not a full-time RVer, it's important to know how to keep your fresh water tank filled while on the road. Depending on your RV setup, you may need to take different steps to keep your water from going stale. In this article, I'll walk you through everything you need to know about keeping your RV's fresh water tank topped off. Read on for tips and advice.

How long can you actually keep fresh water in an RV tank?

As stated earlier, this depends on many different things. But the main rule of thumb is to not leave water in your rv tank for more than two weeks. This is because water can go stale, and sometimes actually develop algae after this amount of time. If you need to leave fresh water in the tank for an extended period of time (say before your next big trip), make sure to treat it with chemicals or run it through a filtration system.

Why you need to test your water?

Testing your water is essential to keeping your whole system up and running. This is because tanks can grow bacteria, algae, and even moss in the tank. All of these things will cause problems once they get into your drinking water supply.

How often do you need to test your water?

This depends on where you live and how much water you put in per day. In some areas, it may be beneficial to test every time you add fresh water to your tank, while other places might require testing only a few times a month.

Check with local regulations before treating or removing contaminants from natural water sources. Some areas prohibit tampering with natural reservoirs.

If any of the following is found, the whole system should be flushed:
  • Chlorine taste or smell
  • Rust particulates
  • Cloudiness
  • Dirt
  • Silt

It's clear that you should start with clean, fresh water before filling your tank. The average person uses about 30 gallons of water per day for household needs. This includes taking showers, brushing teeth, doing laundry and dishes, watering plants, etc.

What happens if the water is not good enough for drinking?

Contaminated or stale water is bad for health. These tyypes of water can cause illness and infection.

What can be done to purify fresh water?

Your best bet is to use a high quality water filter. A good filter will remove particles and minerals that cause bad taste and odors. It will also remove any microorganisms that may be harmful if they are present in the water.

A charcoal filter or granular activated carbon (GAC) removes chlorine, organic chemicals, and some contaminants such as herbicides, insecticides, solvents, etc. Activated carbon filters out chlorine as well as undesirable tastes and odors due to some organic chemicals such as phenols or some industrial solvents which might affect some people's health alarmingly if consumed over a long period of time.


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How to Sanitize Fresh Water Tank Your your RV?

Below will be a step by step guide for you to follow to sanitize your fresh water tank the right way.

  1. Drain your water heater completely.
  2. The low point drains should be the next to be drained.
  3. Next you should drain your holding tanks.
  4. You then need to add about a 1/4 cup of bleach to your tank for every 15.Gals of water in your tank.
  5. You should then fill your fresh water tank with potable water.
  6. After the tank is full, turn on one of your faucets and let it run until you can smell bleach coming out.
  7. Turn the faucet off and take your rv for a drive around town and try to go around as many turns as possible for the water and bleach mixture to slosh around as much as possible.
  8. After parking your rv, let the bleach and water mixture sit in your tank for around 10 to 12 hours.
  9. The next step will be to drain the water and bleach mixture from your holding tank.
  10. When the tank is empty of the bleach and water mixture, fill it up with clean drinking water.
  11. Turn on your faucet and let it run until you can no longer smell any bleach.

If you want to be extra cautious to not have any bleach in your holding tank, you can repeat step number 9 to 11. Only difference is that this time you wouldn't be draining as much bleach as before.

Signs that show when it's time to change out your tank

As with many other things created in a factory, your water tank also has a lifespan. It's been estimated that a fresh water tank can last up to ten years before it starts giving problems. However, there are some signs that you can look for if you want to check out the quality of your holding tanks.

  1. Smell
  2. If your holding tank has gotten really smelly then it might be time to check into buying a new one. This is especially true on those instances when the smell will not go away no matter how much you try and clean your RV toilet bowl or drain the water from or bleaching your fresh water tank with or without using chemicals such as bleach.

    If this happens, make sure to change out the fresh water tank as soon as possible because having bacterian infected stagnant water in your RV can cause respiratory problems.

  3. Chemical content in the water
  4. If you keep your fresh water tank around for too long or reuse the same water over and over again then you are definitely going to run into problems with chemical buildup in your tank because distilled water will accumulate chemicals when it is left standing for a long time. If there are noticeable chucks of white substance on the sides of your fresh water holding tank, then this is most likely calcium build up that has formed from hard tap water.

    This usually forms when people are running their freshwater system by using more than one source of tap drinking water and mixing these together, or if they live somewhere humid where there is high amounts of condensation forming inside of their RV. This is not healthy for your tank and will corrode it overtime.

    One way to get rid of this calcium build-up is by adding vinegar to the system, which can help you dissolve all of that gunk into a chunky mess that will flush out easier with running water. If vinegar does not work, then try using boiling hot sodium carbonate solution (Washing soda) instead, but be sure to use an old pot because sodium carbonate solution eats through metal. Another chemical option is Muriatic acid, but this should only be used when there are no plastic lines inside of your freshwater system because this is so strong that it could eat away at the hose itself.

How much does a new tank cost and how do I install it myself or get someone else to do it for me?

New fresh water tanks can be costly depending on the size your rv requires. The average cost of a new tank is around $200-350. Make sure to find a rv store in your area from which you can get the best price for a new tank without sacrificing quality.

It will be much cheaper to have a professional install one, but if you do not know anyone, the cost of materials and renting a small tool from your local hardware store may be enough to make it your while.

Depending on how complicated your installation process is you can use different types of materials such as steel or plastic for the freshwater tanks themselves. Using steel might be very detrimental to many people who want something that is corrosion-resistant and lighter in overall weight.

What do I need to dispose of when I dispose of my old water in my rv?

When disposing of your old water, make sure that it is at least 100 feet away from any fresh water source such as wells, rivers and lakes because RV waste could contaminate these sources. Also, do not dump it into sewers! Sewers are connected directly to wastewater treatment plants, so if you try dumping RV waste into the sewer then this leads right back into our public drinking supply.

What are some economical ways of getting fresh water, and where can I find a place near me that sells clean, filtered drinking water by the gallon or case so I don't have to worry about running out of supplies again?

One of the best places to get clean, filtered drinking water is getting filters from a company called BWT. Their products are 100% recyclable and they recycle up to 85% of the materials in their filters.

By knowing the capacity of your tank(s) you can determine how much water you can store before needing to get it refilled, allowing you to plan ahead if that's an option for you.

You can usually purchase fresh drinking water by the gallon at places like campgrounds, reststops, state parks, or cabela's. These different places will allow you to fill up your fresh tank in a matter of a few minutes and then be on your way.

You have to be careful of filling up at many different sources because many times these places also have chemicals in their water. You can usually find out by reading the signs near the faucets, pumps, etc.

The best way to keep fresh water is to use a bladder inside of your fresh tank to store it in when it's not being used (i.e., you're full and don't need anymore for awhile). These bladders make sure that all bacteria stays on the outside where you cannot drink it and they are easily emptied when necessary.

What are the risks of not changing your water supply in an RV tank?

There are many differentrisks associated with not changing the water in your rv on time. These can range from simple things like having bad tasting water to more serious issues like growing algae in the tank.

What is the best way to store fresh water?

The best way to store fresh water in your rv tank is in a bladder that goes inside of it. This way, the outside plastic does not come in contact with any of the contents and you can easily remove them when necessary without compromising anything else.


It can be a bit confusing to know how long you should keep fresh water in your RV tank. One rule of thumb is that you should drain the tanks and refill with clean water every 2 weeks, but this may vary depending on where you live or travel. If you have any questions about what’s best for your specific situation, just ask us using the contact page! We are happy to answer all of your queries so that we can help make sure that everything works as it should.

About Author:

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Hi, I'm Kevin Pommells, a lover of camping and the great outdoors as everyone says nowadays. I'm also a passionate soccer fan and the proud owner of, a website dedicated to helping campers and outdoor enthusiasts make the most of their adventures. With years of experience exploring the wilderness and a deep love for the sport of soccer, I'm always looking for new ways to combine my two passions and share my knowledge with others. Follow me for tips, tricks, and insights on all things camping and outdoor recreation.

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