As an RVer, you’ll have to learn all kinds of new things. It just comes with the lifestyle. One of these new things is dealing with the RV black water tank. It’s a yucky but essential job. And as you can imagine, it isn’t something you want to mess up!
Keep reading to learn everything you need to know about your black tank. (And maybe more than you ever wanted to learn!)
Table of Contents
What Is an RV Black Water Tank?
The RV black water tank is a holding tank for human waste. It holds everything that goes down your RV toilet. Sometimes, an RV doesn’t have a grey water tank. In those situations, all dirty water will be routed to your black water tank.
How Does a Black Water Tank Work?
Your black tank holds solid and liquid waste and toilet paper. Your black water tank works a little differently than your grey water tank. With the grey tank, you can sometimes leave the tank open.
You don’t want to do this with a black water tank, though. Instead, you’ll keep the valve closed until the tank is at least 2/3 full. Then you’ll dump the tank.
How Often Do You Need to Dump Black Water?
How often you need to dump black water depends on how much you use your tanks. With more people using the tank, you must empty it more often. If you flush with more water, the tank will also fill up more quickly. But they need a fair amount of water to keep things running correctly – we’ll get into this more later.
Generally, one person can use the black tank for 10 days to 2 weeks. You could probably make it 10 days with two people, but it might get smelly before that point! We recommend dumping your tank about once a week when you have full hookups. It just keeps things from getting stinky!
You don’t want to dump it too often, simply because it’s an icky job. It’s best to empty your RV black water tank once it’s at least 2/3 full. Most RVs have sensors that will tell you how full the tank is. However, they aren’t always accurate depending on your rig’s age (and your tank’s cleanliness).
Using Your Black Water Tank – Avoid The Poo Pyramid
The way you use your black water tank can impact its function. You may not think an RV toilet can get clogged, but unfortunately, that’s not the case. Dealing with the dreaded “poo pyramid” that can build up is not a pleasant task. Here’s how you can ensure your tank works best.
First, always keep the tank closed until it’s ready to dump. Keep the tanks closed even when using full hookups at a campground. If you leave the tank open, your sewer hose will have human waste sitting in (and potentially getting stuck in) it. You also risk all the liquids draining and none of the solids. Then the solids can get stuck and solidify in your tank. Yuck!
Always use RV-safe toilet paper, which disintegrates easier. Regular toilet paper can cause clogs, while RV toilet paper is designed to break down very easily.
If your RV toilet does clog, don’t panic! Instead, read this article: RV Nightmare: How to Unclog RV Toilet
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Finally, use enough water when flushing. If you don’t have enough liquid in your tank, your poo can get stuck when you dump the tank.
RV black water tank size capacity depends on your rig. There’s an enormous range of sizes. You can expect an RV to hold between 15 and 100 gallons. Like we said, a huge range!
If you aren’t sure about your black tank’s capacity, look up the information on the manufacturer’s website. A bigger tank is great for boondocking. The less frequently you need to dump your tanks, the longer you can stay in one place without hookups.
How to Dump Your Black Water Tank
Before you dump your RV’s black tank, connect the RV sewer hose to the wastewater outlet. We recommend using a sewer hose with a transparent elbow, so you can see when it’s done.
Once you hook up, you can open the black tank valve. Leave the valve open until the water stops flowing. After your black tank is empty, then empty the grey tank. Starting with the black tank followed by the grey washes out your sewer hose and helps keep things clean while reducing odors.
For a visual on how to empty a typical RV black water tank, check out this video from the RVgeeks:
Cleaning Your Black Water Tank
Considering what goes into your RV black water tank, it shouldn’t be a surprise that it needs regular cleaning. Keeping things clean will prevent a smelly RV. It also helps prevent problems in the long run.
To clean your tanks, we recommend using a black tank deodorizer/cleaner to help break down waste so your tanks stay cleaner and less smelly. Regular cleaning can also help prevent clogs.
To give your tank a thorough cleaning, first drain the tank. After that, you’ll add some water and a cleaning agent to the tank.
There are several types of cleaners on the market, including liquids or tablets that you drop into the toilet. You can buy a commercial RV black tank cleaner online and in most RV stores.
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If you have waste or toilet paper build-up, you may need to do some extra cleaning. There are a variety of tools for rinsing out your tanks with a high-powered water stream. You can use a macerator, a flush valve, or a tank rinser to get the job done.
For extreme cleaning, you can even hire a professional tank cleaner who can pressure wash the inside of the tank, like in the video below:
A few simple steps will help to prevent issues down the road.
First, clean the tank after each dump. Even though it isn’t fun, staying on top of it makes it more manageable. Another way to prevent issues is to keep your black tank closed. Do this even if you’re staying at a campground.
Next, as mentioned earlier, use an RV toilet paper that dissolves more quickly in water. We also recommend using a holding tank additive and a clear elbow when dumping so you can see the tank and hose are clean. These simple strategies bear repeating because they make a significant difference.
Staying on top of cleaning and dumping your tanks is critical to a happy RV life. If you aren’t already using these tips, it’s time to start now!
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