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RV Black Water Tank Emptying

One thing you will definitely have to deal with while living in an RV is the Black Water Tank Emptying. Eventually, you will have your own black tank story to share with others.

Hopefully, it is one you’ve seen and not actually experienced yourself.

With a few care taking steps about your holding tanks. You can safely handle the gray water and black water tanks with confidence.

RV black tank emptying safely

First, what is the difference between the gray water tank and the black water tank?

What is Gray water?

Gray water consists of all of the water from your drains. This includes the kitchen sink and the bathroom sink.

What is Black water?

The black water holding tank contains all of your toilet waste. It is stored in a separate tank for safety.

Black Water Tank Emptying TIPS

When is the best time to dump?

You really want the black tank to fill up before dumping. This allows the waste to begin to break down. If you empty too often, some of this waste will be left behind and could cause problems in the future.


Do not leave your black tank open when hooked up.

Monitoring levels, once debris like toilet paper get introduced, your black tank monitors will never be accurate.

Always use a visual assessment to let you know where you’re at.


Always use septic safe or RV safe toilet paper.

How to Dump your Black Water and Gray Water.

First, wait until your containers are almost full. WHY? It helps to wait until your black tank is almost full, this gives things time to begin the process of breaking down.

How to empty your black tanks. Order of operations for emptying. gray tank test first, then black tank, then gray tank.
A good order of operations.

Dump a little of the gray water first, to test the system and then shut the valve. This will let you know that everything is working properly and sealed. Allowing you the option to adjust anything before you begin your black tank dump.

Now, you can open your black tank. Let this flow out and stand by watch to make sure everything goes smoothly.

Next, close your black tank and open your gray tank. Allow the gray tank to fully dump.

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Liquid Shocker ClO2 Odor Eliminator

After dumping both the black water tank and gray water tank, do a flush. Your RV probably comes with a system to do this flushing. If you do not have one, you will be using other chemical that you place into the toilet after flushing.

Additionally, It is illegal to dump black water waste any where other than an appropriate dump station, sewer, or RV hook up site.

There are times things get a little smelly.

This handy shocker takes care of the funk.

Toilet Tips

In an RV, the toilet has a foot pedal. This pedal, when pressed half way down will fill the bowl with water without opening the drain. Always add water for each flush. This helps things break down while in the tank.

Flush as little paper as possible. Toilet paper can easily clog up your system. It is a really big deal to have to fix this after the fact. There is no need to flush paper for every little tinkle. Just put the paper in the trash and empty your trash frequently.

Never, ever, ever, place anything else in your RV toilet. Doing so will cause a huge stink-Literally and figuratively.

If it does get clogged- Learn more about unclogging your RV toilet.

This article suggests pouring boiling water down the toilet and says that worked wonders.

You can also snake the drain with a tool like this one:

RV toilet plumbing snake for toilet
RV toilet plumbing snake for toilet

Can I dump my black tank anywhere? No!!!

Black water is not only foul, it’s filled with dangerous bacteria that can spread disease.

Only use an RV dump station to empty your black water tank.

You can also dump remotely using a blue tote.

Blue tote for dumping the black tank system in an RV
Blue tote for dumping the black tank system in an RV

Learn more about dumping remotely in this article:

Related article: How to empty your tanks while “dry camping” or “boondocking”.

What about Composting Toilets?

Composting toilets are a great way to reduce water use and waste. There are several options out there. First from the simple bucket and trash bag to the Cadillac of composting toilets- Nature’s Head.

Composting toilet that can be used in an RV or while RV Boondocking
Composting toilet that can be used in an RV or while RV Boondocking
Natures head composting toilet
Natures head composting toilet


In conclusion, taking these precautionary measures and useful tips will keep your black tank and gray tank healthy. This will keep you far away from a nightmare you don’t want.

Related Articles You May Enjoy:

^ Free Camping resources and Boondocking Near Me

^ Water Resources for RV Camping and Boondocking

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