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The Geo Method

  • 8 min read

Key Points:

  • The Geo Method uses a combination of powdered Calgon (water softener), laundry detergent (soap/surfactant), plenty of water, and often bleach or chlorine (to attempt to control odor). 
  • While The Geo Method can be beneficial for those who are wanting to perform the occasional tank-wall cleaning or attempt to restore misreading sensors, it doesn’t perform all of the necessary tasks required to make it an effective routine tank treatment.
  • The Geo Method does little-to-nothing to break down solid waste and eliminate odors. Because of this, it can lead to clogs and odors, which can take a lot of time and money to fix.
  • The Geo Method kills bacteria, so it cannot be used in conjunction with a bacteria-based holding tank treatment. It will kill off the good bacteria in the treatment, leading to increased possibility for clogs, odors, and misreading sensors.
  • There is a better solution that addresses all 3 of the crucial parts of holding tank maintenance: 1) maintaining working sensors, 2) digesting waste, and 3) eliminating odors. 
  • The Unique Method provides a comprehensive solution to holding tank maintenance. 

Has someone suggested using The GEO Method? The RVing community shares a lot of ideas on ways to clean your holding tanks, but the truth is they may not work as well as reported, including The GEO Method. It's one of the most popular techniques and claims to provide a comprehensive treatment process that will fix and avoid holding tank problems. This article will cover how it works, whether or not it is effective, and other treatment options. Spoiler alert: our analysis leads us to conclude that it does not adequately address all of the holding tank issues that you might run into, so continue reading to learn about our recommendations for the most effective way to clean your wastewater holding tanks.

What is The Geo Method?

Created in the 1980s by Charles Bruni, The Geo Method uses a combination of powdered Calgon (water softener), laundry detergent (soap/surfactant), plenty of water, and often bleach or chlorine (to attempt to control odor). Through his extensive experience as an RVer, Bruni created what he called The Geo Method as a homemade system for treating the interior of your holding tanks. 

Through the process of water softening (using Calgon), organic and inorganic solid waste are less likely to stick to the walls of your holding tank. Laundry detergent or dish soap is also used to help break up any solid waste that may still get stuck to the walls or sensors in your RV and help rinse it away. 

While we agree that some of Bruni’s ideas are helpful, we also believe that proper tank maintenance should go beyond just keeping your tank walls clean. Proper tank maintenance should do three important things:

  1. Digest solid waste so it can’t accumulate anywhere in your tank (including the tank walls).
  2. Eliminate odors at their source without using strong perfumes.
  3. Help remove waste that can accumulate on sensor probes and cause them to misread.

The Geo Method is designed to create an environment where it is difficult for waste to accumulate inside the tank. The theory is that by helping the waste slide out of the tank, you can prevent common issues like clogs, waste buildup, or misreading sensors. 

There are a few fatal flaws with The Geo Method though:

  1. It does nothing to address odors - and odors are a huge problem for RVers. The Geo Method’s best option is to use bleach or chlorine to kill the anaerobic bacteria and eliminate odors. However, by killing the bacteria you are stopping a crucial process of waste breakdown that can and will lead to clogs. So, The Geo Method may help the waste rinse out of the tank, but it also makes it clump up into bigger piles that can cover the discharge port and clog a tank.
  2. The Geo Method is designed to help rinse waste down the line, but to clear the line effectively, waste must be digested. Poop and paper can cause large clumps of waste if they are not broken down before trying to rinse them down the line. The Geo Method recommends the use of laundry detergent or dish soap to help aid in the breakdown of the solid waste. Unfortunately, these types of products aren’t efficient at breaking down paper and protein (poop). They are helpful for breaking up grease, so this process is somewhat helpful in the gray and galley tanks, but it’s inability to break down poop or paper makes it ineffective inside your black tank and clogs are more likely to form.
  3. The nature of The Geo Method is to create a slippery surface inside your holding tank. Yes, this can help prevent waste from sticking to your sensor probes, causing them to misread, but because the chemicals in The Geo Method inhibit waste break down and odor elimination, it’s not a well rounded treatment.

In conclusion, you may want to use The Geo Method on occasion to perform a deep clean on an already well-maintained tank, but to rely on it as a regular treatment process is not a good idea. You are eventually going to end up with clogs and odors.

NOTE: As an effective alternative to The Geo Method, if you would like to perform a deep cleaning on your holding tanks in a way that will promote healthy tanks, instead of exposing yourself to more clogs and odors, read this guide.

Pros and Cons Of The Geo Method

  • The Geo Method can be used effectively to occasionally deep clean your tank. The method can assist in rinsing away solid waste from the interior of their RV black tank.
  • When used correctly, The Geo Method can be an effective way to help prevent misreading sensors.
  • The Geo Method is a alternative to treating your tank with caustic or dangerous chemicals, which is never recommended.
  • The Geo Method does very little to break down solid waste. Though effective at aiding in rinsing out waste, The Geo Method does little-to-nothing to actually break the solid waste into smaller pieces and this can lead to clogs and backups.
  • The Geo Method is ineffective at reducing foul tank odors.
  • The Geo Method can kill beneficial bacteria inside your tank that work to eliminate odors and digest waste.
  • If you are using a bacteria-based holding tank treatment, along with The Geo Method, you may be negating the benefits of the treatment.
  • The Geo Method isn't necessarily an effective treatment process for dry campers (boondockers).In low-water situations, The Geo Method is less effective and odors can become an issue when using the Geo Method.
  • The Geo Method is actually quite expensive when you consider the cost of ingredients over time.
  • The ingredients used in The Geo Method are not readily available and can be difficult to find.

Can You Use RV Digest-It (or other bacteria-based treatments) with The Geo Method?

Many RVers use bacteria-based treatments in their black and gray holding tanks, because they are thebest all-around treatments for the majority of RVers. Many proponents of The Geo Method don't fully understand how detrimental it can be inside tanks that are treated with bacteria-based treatments.

It can be easy to think that a process like The Geo Method will solve all of your holding tank problems, but remember, digesting waste and getting rid of odors is also important and The Geo Method falls very short on these two aspects. The Geo Method does a good job rinsing the interior walls and sensors in your RV black water holding tank, but without fully digesting the solid waste inside your tank, it’s only a matter of time before you experience clogs and odors. 

Here’s why The Geo Method won’t work with a bacteria-based holding tank treatment, like RV Digest-It:

  1. By softening the water in your tank, The Geo Method raises PH levels too high for good bacteria to survive. This happens because the ingredients in Powdered Calgon cause a chemical reaction with hard water that raises the water’s PH levels. This will remove the calcium and magnesium from your tank walls and sensors, but the higher PH levels will also kill off all of the good bacteria that you are using to treat your tank. 
  2. Aerobic bacteria (“good” bacteria that are odorless) will most likely die off in the high-PH environment The Geo Method creates, while “bad” anaerobic bacteria (which create that “sewer smell” by releasing methane and hydrogen sulfide gas) will often survive. This means you will probably experience really bad odors if you use The Geo Method because these “bad” bacteria are more likely to thrive in high PH environments. 
  3. The bleach or chlorine added to your tank will also kill bacteria.The Geo Method prescribes using bleach or chlorine to eliminate odors, but bleach and chlorine are also specially designed to kill bacteria. Bleach and chlorine will also cause waste to accumulate and lead to clogs.

Again, The Geo Method has its positive aspects, but after looking at the big picture we can see that this method doesn’t address the whole-tank approach that is truly needed. 

Now that we’ve effectively proven that The Geo Method falls short, where do we go from here? Introducing The Unique Method. 

The Unique Method

The Geo Method effectively solves the issue of misreading sensors, but as noted earlier, there is much more to tank maintenance.

There are 3 aspects of proper tank maintenance: 

  1. Maintaining properly working sensors
  2. Digesting waste
  3. Eliminating odors

While the Geo Method has its benefits, there is a better solution that addresses all three of the points above. We recommend that you use our comprehensive treatment process, The Unique Method.

The Unique Method is a proven holding tank treatment process that we have meticulously developed over the years through in-depth conversations with campers of all types, followed by scientific research that addresses the issues brought up in these conversations. Our process is easy to follow and will virtually eliminate all problematic tank odors, prevent clogs and pyramid plugs, and ensure that your tank sensors continue to read properly. With The Unique Method, we've taken the confusion out of tank maintenance by developing a very simple yet robust program that is hands-down the most effective process available today.

Read in-depth about The Unique Method here!

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Many people believe that The Geo Method is a good solution for sensor problems and that it can be used to successfully ensure that your tanks remain clean and free from residue. This is true to some extent. However, it is not a perfect nor a complete solution to treating your RV holding tanks; in fact, it may cause you more problems.

The Geo Method, in our opinion, is only one solution to a complex problem. By only addressing one of the key issues that come with holding tank care, The Geo Method fails to provide an all-inclusive tank maintenance process.

Of course, this is just our opinion—though it is well-researched and thought out. We would love to hear your thoughts on The Geo Method! If you have any questions, concerns, or comments, please feel free to reach out to our customer support team. We would love to answer your questions about The Geo Method!

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