What Is An RV Pyramid Plug?

August 06, 2020

Learn how to solve an RV Pyramid Plug. Diagnose and fix clogged waste in your RV black tank. Unique Camping + Marine

Key Points:

  • A pyramid plug is a literal pyramid of poop and toilet paper that starts building on the tank floor and eventually blocks the bottom of the toilet line
  • Pyramid plugs are typically caused by leaving the black tank valve open
  • Pyramid plugs share the same symptoms as a blocked plumbing line that connects the toilet to the black tank, so be sure you identify the type of clog before taking steps to clear it
  • Clearing a pyramid plug can be accomplished by following our easy instructional steps
  • Preventing pyramid plugs starts with following The Unique Method

We've all experienced a toilet clog at home. Even a simple plunge is something no one ever wants to deal with. In an RV, clogs can form into a whole other shape of annoying, specifically the shape of a pyramid. Yes, the name pyramid plug is an accurately descriptive name. It's a type of RV toilet clog that is a typical problem for hook-up campers who leave their black water valve open, even on an occasional basis. In this guide, we'll describe exactly what a pyramid plug is, how it forms, and will provide resources so you can diagnose and unclog your RV holding if it ever becomes a problem.

What is a Pyramid Plug and How Does It Develop?

A pyramid plug is literally a pyramid of poop and toilet paper that builds up right underneath your toilet line. This usually happens when hook-up campers leave their black water valve open thinking all the waste will automatically flow right into the sewer. The problem is that most RVs have a relatively flat-bottomed black tank; if the black valve is open, any liquid that is added trickles out leaving a nearly dry tank, which means solid waste that is added starts piling up right under the toilet line. Because there’s no liquid in the tank, the solid waste has no way to easily slide out of a flat-bottomed tank. Toilet paper mixed in with the solid waste acts as a binding agent and helps the pile stay intact so that it continues building higher and higher until it is touching the toilet line and blocking the addition of anything (even liquid) to the tank.

Pyramid Plugs In RVs, what they look like and what it takes to remove one. Unique Camping + Marine

Clearing pyramid plugs doesn’t have to be complicated or stressful when using a bacteria and enzyme treatment (like Unique RV Digest-It), but you need to be sure about exactly what kind of clog you have. Sometimes you don't have a pyramid plug at all; a blocked toilet line shares the same symptoms, but there are different unclogging steps to take depending on the type of clog.

Diagnosing a Pyramid Plug

You may think you have a pyramid plug, but as we said above, a blocked toilet line shares the same symptoms as a pyramid plug and requires a different method for clearing it. Use the diagnosis tool below to confirm you have a pyramid plug or determine you have a different problem.

Add water to your black tank through your RV toilet bowl.

  • If the water quickly collects in the toilet bowl and you have left your black water valve open for any period of time, you probably have a pyramid plug. 
  • If the above diagnosis does not fit your situation, you probably have some other kind of RV toilet clog. Refer to the Clearing RV Toilet Clogs guide for more information on identifying the type of clog you have and how to clear it.

Clearing a Pyramid Plug

So you are sure that you have a pyramid plug and are wondering what you can do to get rid of it? When you use our easy-to-follow steps and Unique Tank Cleaner, clearing a pyramid plug is not complicated or stressful. Refer to the Clearing a Pyramid Plug section in the Clearing RV Toilet Clogs guide. And as always, if you are having trouble resolving your RV toilet clog issue after following our guide, contact us any time and we will help you unclog your RV black water tank!

Preventing Pyramid Plugs

Prevention of any type of RV toilet clog starts with following The Unique Method, our proven process for caring for RV holding tanks. It is a 50/50 approach that requires 50 percent the right care habits and 50 percent the right products. We always recommend using Unique products because they were developed with The Unique Method in mind, meaning you will get the best possible results when you pair our method with our products. The most important things you can do to prevent pyramid plugs is:

  • Always leave your black water valve closed unless you are actively dumping a full tank
  • Add lots of water every time you flush
  • Use a high-quality bacteria and enzyme treatment product (like Unique RV Digest-It)

Of course, if you are experiencing a clog right now, we invite you to check out our Clearing RV Toilet Clogs guide to restore your RV toilet to full functionality and be ready for your next outdoor adventure!

Guide: Preventing Clogs in Your RV Holding Tank

Guide: Why It's Crucial to Keep Your RV Black Water Valve Closed

Guide: Why Using Lots of Water in Your RV Toilet and Holding Tanks is Crucial


Pyramid plugs don’t have to be that thing you fear while enjoying your RV if you just remember a few things from this article:

  • A pyramid plug is a literal pyramid of poop that blocks the bottom of the toilet line, and they form when there’s no liquid in your tank (typically because the black valve is left open)
  • Confirm that you have a pyramid plug before working to clear it as there are different steps for fixing different types of clogs
  • Preventing pyramid plugs is as easy as keeping your black valve closed unless actively dumping a full tank, using lots of water, and adding a high-quality bacteria and enzyme tank treatment.

Adopt The Unique Method

You bought your RV so you could enjoy life and spend time with family and friends. The last thing you want to do is waste precious time and money on fixing wastewater holding tank problems. Keeping your tanks in peak operating condition doesn’t have to be hard, confusing, or expensive if you follow our proven process: The Unique Method.

The Unique Method is a comprehensive tank care plan that we developed after years of conversations with real customers facing real problems. The Unique Method provides you with simple, preventative steps to stop odors, clogs, and sensor problems before they start so you can spend less time worrying about your holding tanks and more time enjoying the freedom and adventure of RVing. Try it yourself and see why thousands of campers trust their RVs with The Unique Method every day.

If you need more help with anything covered in this guide or simply have a comment, we’re here to help you anytime!

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