Does The Geo Method Actually Work?
From campfire discussions to online forums, the Geo Method has been recommended for years as the black and gray water holding tank ultimate cleaning process. The general idea is that by following the Geo Method you’ll be able to unclog tanks (or prevent them from clogging in the first place), prevent sensor problems and eliminate toilet smells. But, does it actually work?
In short – not really. The theory is that combining Calgon (water softener), Dawn liquid dish soap and sometimes bleach or Pine-Sol with a few gallons of water you can magically clean the holding tanks, which will prevent every known RV wastewater problem.
Here’s the key problem with the Geo Method: It makes a lot of promises that don’t actually turn out to be true in reality.
The Geo Method is often recommended for its supposed ability to lift waste off the walls of the holding tank with the surfactant nature of the Dawn soap and the water softening ability of the Calgon. However, the reality is, this system is not very great at doing this.

Sure, Dawn is a great solution for breaking down grease and lifting it off a surface, but grease is not the major issue inside a black tank – paper and human waste is, and Dawn does very little to break down this type of waste.

Additionally, Calgon is not intended to be used as a surfactant that removes waste from a black tank, and so we’re not surprised when it doesn’t do a very good job at that specific task.

The problem with bleach or Pine-Sol is that they are antibacterial agents. In other words, they are designed to kill all of the bacteria inside the hold tank, and by doing so, eliminated odors. As you probably know, bacteria play a vital role in holding tanks and just killing them is a bad idea. It will eventually lead to clogged tanks, and using products like bleach or Pine-Sol will more than likely cause more odor issues in the long run than they will solve. If you’d like to know more about how bacteria benefit holding tanks, and why you want to support them and not kill them, read this post.
To add to the problem, some of the ingredients in the Geo Method also have the ability to damage seals and gaskets. And we haven’t even mentioned how hard buying Calgon is!
Here’s the thing… we’ve heard from numerous RVers over the years how excited they were to use the Geo Method, and how upset they were when it didn’t work. Understand this, people tend to gravitate towards the Geo Method because they are using holding tank treatments that don’t get the job done, and they’re looking for a solution. The question we’d ask is, why would you resort to using random ingredients that weren’t made to be used in RV holding tanks when there are very effective products designed for this very purpose, and a treatment process that is built to specifically address tank odors, waste accumulation, and misreading tank sensors? It’s an illogical jump that feels desperate, and there is a much easier solution.
Instead of the Geo Method, we recommend The Unique Method along with a high quality holding tank treatment. Thousands of people use The Unique Method everyday and have virtually eliminated their holding tank troubles, and you can too!
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