Tuesday, November 28, 2023


Three ways to stop RV holding tank odors and make the sensors work again

By Cheri Sicard
Get ready for an RV holding tank odor master class in this amazing video. In it, TR Bowlen tackles the topic of holding tank odor, one of the most common RVer complaints, along with how to keep your holding tank level sensors working properly.

TR says there are three easy things you need to do in order to maintain your RV’s holding tanks and eliminate holding tank smells. Of course, the video gives more details, too, but the steps break down to:

  • Properly flushing the tanks
  • Adding 1/2 cup of Borax and 2-3 gallons of water after dumping and flushing
  • Adding 1/2 cup Dawn dish liquid (optional)
  • Using plenty of water

TR calls his odor-proof holding tank theory the Bio-Geo method and says it is a science-based method for controlling holding tank odors. He even offers a DIY checklist you can keep in your RV. Download that here.

Do watch the video, because this treatment is not necessary every time and he goes into detail on how to make it work properly.

When TR bought his current motorhome, the previous owner had not taken care of these issues and it came with a serious holding tank odor problem. In addition, none of the tank sensors were working.

In order to solve his problems, he started researching the topic and discovered the “Geo Method.” This involved introducing detergent, bleach, and water softener into your holding tanks, and flushing from full tanks. He was satisfied with how the method worked but soon discovered that he had traded holding tank smells for the smell of chlorine bleach. Not to mention, bleach itself can be problematic.

So, no bleach, but TR found a far better natural alternative in Borax. The video even covers the science behind this new method and how Borax changes in water and how it can work to keep your tanks and sensors clean.

His explanation of the holding tank level sensors and why they stop working was especially beneficial. I have yet to encounter any RV whose sensors don’t eventually stop working. But this is an easy-to-fix issue in most cases.

He also covers doing a “road flush” for thoroughly cleaning both the black and gray water tanks, and how they differ.

Another bonus, this method is extremely economical, costing less than commercial holding tank odor treatments. And, double bonus, you can clean your toilet bowl at the same time as when you add this treatment to your tanks.

Once everything is working properly and you have eliminated the odors, you should only need to do this every 4th or 5th time you empty your tanks!




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TR Bowlin (@guest_245896)
4 months ago

Hi. I have updated the video. Here is the link. https://youtu.be/RgCK_wV7TLI

Cheri I am happy to share the cover slide or anything else in the video with you. Just let me know what you need.

Diane McGovern
4 months ago
Reply to  TR Bowlin

Thanks, TR. I’ve passed your message along to Cheri, in case she doesn’t notice it in the comments. Have a good night. 😀 –Diane at RVtravel.com

Steve (@guest_213462)
11 months ago

This makes overall good sense

Gary Bate (@guest_212673)
11 months ago

I have a 2009 Winnebago View purchased used 3 years ago. It was well maintained. We’ve put a lot of miles on it crisscrossing the country several times. We used to get tank odors when driving. I’m now more vigilant and do 2 – 3 full tank flushes after several dumps. I store it between trips with a full clean black tank with a orange pod. Have no odor problem anymore, sensors have always worked fine.

Rick (@guest_212653)
11 months ago

I just watched another YouTube video that showed what happened to the borax after sitting in a jug of water for a short period of time – it turned to hard large crystalline chunks. Yikes! How is that happening and yet many people said they’ve been using this method for years (with apparently no issues)??

TR Bowlin (@guest_212707)
11 months ago
Reply to  Rick

That is sitting in 1 gallon of water, so naturally, it will not dissolve into the one gallon of water. Your holding tank is 30 or more gallons, and the borax will dissolve in your holding tank. The demonstration does not represent the real-world use case. I’ve used this method for seven years with not one problem.

TR Bowlin (@guest_212630)
11 months ago

Thank you for the article post. I am very happy when people share this video. It truly is the easiest and least expensive method to STOP the STINK. I am also happy to address specific problems related to maintaining the holding tanks posted in the comments on the video. Be watching for a huge update to the video early next spring. After three years of answering viewer questions (almost 3,000 of them) and nearly 1 million views, I have a few updates to make. But, in all of those comments, there has not been one that said it does not work! Thanks again!

Cheri Sicard (@guest_212845)
11 months ago
Reply to  TR Bowlin

You always do such a great job on your videos. Thank you TR!

B N S (@guest_212596)
1 year ago

TR,s Method Works Very Well !

TR Bowlin (@guest_212635)
11 months ago
Reply to  B N S


DW/ND (@guest_212573)
1 year ago

This is an excellent, easy to watch and listen to video. Whether you use the “method” or not, the video is highly educational – if you want to understand how it all works. Thanks for providing it Cheri!

Carol (@guest_212563)
1 year ago

Is there a difference between Borox and Boroxo? (Liquid vs. powder?)

Carol (@guest_212565)
1 year ago
Reply to  Carol

Borax vs. Boraxo? I am not familiar with this product but will definitely give it try!

Cheri Sicard (@guest_212615)
11 months ago
Reply to  Carol

I believe Boraxo is just a brand name of Borax.

TR Bowlin (@guest_212632)
11 months ago
Reply to  Carol

I kept calling it boraxo because my grandfather ran a Chevron service station for 4 decades, and when I was young, I hung out there a lot. One of my jobs was cleaning the bathrooms and refilling the ‘boraxo’ powdered soap dispensers. I am afraid that it is permanently stuck in my head. You should use powdered borax.

Gary (@guest_212555)
1 year ago

The “Geo” method uses Calgon (water softener) and liquid laundry soap (doesn’t foam up).
Did not click on the video.

Steve (@guest_213456)
11 months ago
Reply to  Gary

Thanks, the ‘GEO’ method has been around and recommended for many years and as you note, it calls for a water softener like Calgon. Not taking away from video, but agree with you.

Drew (@guest_212550)
1 year ago

I’ve done it all. Happy Camper does it without any hassle. They don’t sell it in Ca. anymore though…..that should tell you it works!

B N S (@guest_212595)
1 year ago
Reply to  Drew


Joe (@guest_212532)
1 year ago

I have been using this method for years however I do use a small amount of Rid-X after every dump in each tank. The gray tank if not maintained properly can stink worse than the black so our first method to control odor is to wipe all dishes, pans and such with our napkins. Second is a screen in the drain and use a dishpan when we want to soak something so all water needs to pass through the screen collecting remaining food scrapes. I never used a citrus cleaner in the tanks while driving and am interested in the outcome. The capacitance probes and monitoring system are not much different than what is used in industrial sewerage systems which also have similar issues over time.

Jim Berkner (@guest_212715)
11 months ago
Reply to  Joe

We have also used Ridex since the first of our trailers had holding tanks in 1986, and on porta potties before then. One tablespoon down BOTH the black and grey water holding tanks after each dump. No extra water added between outings. No problems and no chemical odors. Also used it for 40 years on our rural home with a septic system.

Melissa (@guest_212523)
1 year ago

I found this method highly effective and have been using it for about 18 months. I even have it printed out so I can show it to others who have the same issues with their tanks.

Bob M (@guest_212522)
1 year ago

While his method may work for his RV, the bottom line is the tank sensors are junk that the rv manufacturers install. Mine stopped working the 2nd year after manufacture. Had the dealer check, he said they work. Took it home started using after Memorial day and they don’t work. Even the fresh water tank sensor don’t work. Jayco uses some junk equipment in the RV’s.

Ed D. (@guest_212537)
1 year ago
Reply to  Bob M

Bob, you are totally correct. I have tried the Borax method and every other method I have ever found on line. None of them work. Even the products that are sold specifically to clean sensors are just a big waste of money.

TR Bowlin (@guest_212634)
11 months ago
Reply to  Bob M

Soak, soak, soak the tanks. The issue is not the sensors, it is that they get gunked up with material in the holding tanks and stop working. It works for me because once I got my sensors working, I flush the tanks thoroughly. I discuss this in the video, but the short answer to fixing them is soaking the tanks with fresh water, borax, and dawn. This softens the gunk accumulated on the sensors stopping them from working, and allows it to wash away.

Greg S (@guest_213381)
11 months ago
Reply to  TR Bowlin

Will the Boraxo powder damage a macerator in the toilet?

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