Choosing the Right Products or Methods for Cleaning RV Tank Sensors

August 26, 2021

How to choose the right products to fix misreading sensors. Unique Camping + Marine

Key Points:

  • Bacteria and enzyme tank treatments are the all-around best choice
  • Scientifically, the Geo Method and the ice and driving technique do not deliver the results they claim
  • Dawn Ultra dish soap is fantastic for cleaning grey/galley tanks, but ineffective when it comes to black tanks
  • Drain openers and chemical cleaners should avoided
  • Adopt The Unique Method to avoid sensor issues in the future

Maintaining functioning tank sensors starts with The Unique Method, which is a 50/50 approach: 50 percent in the type of products you use and 50 percent in the care habits you practice. Many people dealing with misreading holding tank sensors want a quick solution, but quick solutions rarely give them the long-term fix they desire. To ensure long-term functionality, you need to consistently adhere to the two elements of the 50/50 approach:

  1. Using the most effective cleaning products
  2. Performing the correct maintenance processes

But current sensor issues may not be resolved by simply practicing the 50/50 approach. If you have not been practicing the right tank care habits and are dealing with stubborn sensor problems right now, let’s take care of it with the right cleaning product first. However, even with the most effective products, it can be time-consuming as multiple treatments might be required. There are lots of product options when it comes to cleaning RV tank sensors, but you should know the benefits and drawbacks of each before making a decision. Some of the categories of RV tank sensor cleaners and methods are:

  • Bacteria and enzyme blends
  • Surfactants (soaps) and The Geo Method
  • Dawn Ultra dish soap
  • Ice and Driving Technique
  • Drain openers and chemical cleaners (not recommended)

Bacteria and Enzyme Blends

Out of the various bacteria and enzyme sensor cleaners on the market today, Unique Sensor Cleaner is by far the highest quality and most effective treatment because it’s packed with superior ingredients, specially formulated strains of the highest quality bacteria, and the highest concentrations of active ingredients. The bacteria and enzymes that are added to the black tank(s) by using this type of product work together to begin breaking away the debris stuck to the sensors. After letting the black tank sensor cleaner sit in your tank for many hours (ideally 72+ hours when using Unique Sensor Cleaner), you can dump the tank and perform a thorough rinse to knock off any remaining residue.

Keep in mind though, sensor cleaning products must be used correctly; pouring a bottle of sensor cleaning fluid into your tank and walking away will not fix the problem. If you add a cleaning solution to a half full tank, only the sensors on the bottom half of the holding tank will be cleaned because the low water level prevents the cleaning solution from reaching the upper half of the sensors. It also needs lots of water in order to reach all the affected sensors and clean them efficiently. Unique Sensor Cleaner is the most effective sensor cleaner out there, but only if it is used as directed.

Note: For more information on how to use Unique Sensor Cleaner to restore malfunctioning black tank sensors, refer to the How to Clean and Restore RV Wastewater Sensors guide.

The great thing about bacteria and enzyme sensor cleaners is that they are very easy to use, quickly effective, typically less expensive than the large quantities of soaps and detergents used in surfactant-based remedies, and don’t require movement to help the cleaner slosh around in the tank; stationary units can still see great results from using this type of product. Be cautious though when choosing a bacteria and enzyme sensor cleaner because so many of the other bacteria-based cleaning products have low bacteria concentrations and inconsistent strains. We vary our bacteria strains and select strains that produce specialized enzymes to better target certain types of organic matter. Bacteria and enzyme blends can sometimes be on the expensive side, but there is less chance for humans, the environment, and your tanks to be negatively affected.

Cleaning RV black tank sensors is a tough job, so make sure you’re correctly using the most effective tank sensor cleaner on the market that will provide peace of mind when it comes to safety: Unique Sensor Cleaner. Misreading black tank sensors can be a tricky problem to solve and even with Unique Sensor Cleaner can sometimes require multiple treatments. Remember, if the first treatment doesn't fix the problem, it's not necessarily because the product is ineffective; the product must be used as directed, more treatments may be needed to remove stubborn debris, or sensors could just be broken altogether. No treatment product will fix a broken sensor. Whatever the situation, we're available to answer questions and help you get the best results, so contact us any time. 


Surfactants and The Geo Method

The Geo Method is one of the most popular tank and sensor cleaning techniques passed around the RVing community. However, we’ve thoroughly analyzed The Geo Method from a scientific perspective and reject the idea that its chemical combo is able to effectively and comprehensively clean or loosen waste; we always prefer to lean on consistently effective, scientifically-based solutions that we can biologically explain. The chemicals used in this method will also kill bacteria inside your tank, so if you intend to use bacteria and enzyme treatments in your tank, we do not recommend using The Geo Method.

The Geo Method claims to clean RV tanks and sensors using a combination of a water softening product called Calgon and surfactants like dish soaps or laundry detergents. Surfactant is just a fancy way of saying soap, and they are often recommended as a way to clean the inside of RV holding tanks and sensors. Softened water allows surfactants to work better, meaning it will foam up and be more efficient at cleaning the buildup you are targeting. Allegedly, the Calgon coats the walls of the tank and the sensors, making them slick so that debris and residue that normally sticks to them slides right off, but testing and analysis does not confirm that this is the case. Calgon doesn’t “coat” much of anything but instead probably just changes the chemistry of the water, preventing calcium buildup on a microscopic level, and since you’re not trying to prevent calcium buildup in your black tank, it’s clear to us that Calgon will not do much to dislodge already built-up waste residue or even prevent new residue from adhering. 

The Geo Method isn't proven, and most frustrated RVers we talk to report that they've tried this technique many times without achieving the desired results. Because of the inexact nature of this method, you may have to play around with measurements and ratios to try to achieve the result you want, but the truth is, it’s possible you may not be able to achieve clean RV tank sensors with this method. 

Note: For more details on the merits and pitfalls of this technique, refer to The Geo Method guide.


Dawn Ultra Dish Soap

You can certainly try The Geo Method on gray or galley tanks but we have found that the best sensor cleaner for gray tank(s) is Dawn Ultra dish soap. Gray/galley tank sensors can become blocked with oily residue from food grease, soaps, shampoos, conditioners, and lotions. This type of buildup requires a different kind of cleaning product: a grease-eater, and the best one out there is Dawn Ultra dish soap. While it seems counter-intuitive to add more soap to a tank with sensors already covered by soap scum and grease, this particular dish soap is fantastic at attacking the grease and scum buildup without leaving its own residue behind. We recommend regularly using bacteria and enzyme treatments in your gray/galley tanks, so washing your dishes with Dawn Ultra is also a good idea because it also does not contain antibacterial elements. 

Dawn Ultra is very effective at cleaning gray tanks, but grease-eating products like it will have basically no cleaning or breakdown effect on black tank waste like feces and toilet paper. There shouldn’t be much grease in your black tanks, unless you’re dumping food waste down the toilet; there may be a miniscule amount of grease from the waste breakdown process, but not enough to necessitate the addition of Dawn Ultra to your black tank(s). When it comes to black/gray combo tanks, we recommend cleaning sensors as if it was a black tank, and when you’re finished, you can always clean it as you would a gray tank with Dawn Ultra, just to ensure that both types of potential grime on the sensors are thoroughly cleaned off.


The Ice and Driving Technique

The ice and driving technique has been around for a while. The basic idea is that you put a certain amount of ice and a small amount of water and detergent/dish soap in your tank and then drive around for a few hours to let the mixture slosh around in the tank. The ice is meant to be a scouring agent for the walls of the tank and the detergent offers additional cleaning assistance, but the advised proportions of water, ice, and detergent are difficult to master and you would still have to drive around like a maniac for the mixture to even reach the top sensors. And when you think about it, cleaning grime off of something usually works better with hot soapy water, not ice cold water. You may see better results by filling your tank with hot water and detergent and driving around, but from our experience with customers who have tried this technique, they report it is pointless, unsuccessful, and a waste of time and money.


Drain Openers and Chemical Cleaners

If the above techniques don’t work for you, chemical cleaners like Liquid Plumbr, Drano, and Pinesol are popular choices and are even recommended in some RV manuals. These products may contain chemicals like acids, lye, or potassium hydroxide to physically burn away the debris that is stuck to the holding tank sensors. These products are available in many retail stores at more reasonable prices than bacteria and enzyme treatments and work very quickly to burn off the residue, but they can easily damage your sensors, valves, and seals if not used carefully; these corrosive chemicals can also have negative effects on humans, pets, and the environment. And since chemical-based products kill bacteria, you'll need to make sure you thoroughly rinse the tank clean of any residual chemicals before adding bacteria-based treatments.

In some very rare cases, these types of cleaners may be the only thing strong enough to eliminate the stubborn residue, but you'll need to weigh their pros and cons based on potential tank damage, safety, cost, and effectiveness. Always check your RV user manual before using cleaners like these; using a chemical cleaner not recommended by the manufacturer could result in damage that may not be covered by a warranty. Generally, we recommend avoiding the use of these chemical cleaners because of the safety concerns and the fact that it will counteract any bacteria-based cleaners or treatments you want to use. If you are desperate to fix a sensor issue and have tried everything else but do not want to risk using the chemical cleaners, you can also install external sensor readers that will have a much lower probability of malfunctioning.

Now that you know what all the options are, it's up to you to weigh the risks and rewards of each choice and know that we're happy to answer questions or help you solve a problem that might seem hopeless.

Contact Us


Best Practices for Preventing Sensor Problems

Sensor issues can often seem overwhelming, and they may not be fixed overnight, but there are certain steps you can take to prevent them in the future. From our conversations with thousands of RVers, we’ve developed a comprehensive, proven wastewater treatment process called The Unique Method. Below, we have provided a high level checklist of The Unique Method's practices that will help curb sensor problems in the future, but we highly recommend reading through the entire guide on The Unique Method to get the more extensive information:

  • Use your tank valves correctly (black is always closed; gray is open when on hook-ups and closed when dry camping/boondocking).
  • Treat your holding tanks with a high-quality bacteria and enzyme product (preferably not chemical cleaners).
  • Fill your toilet bowl with water before you use it.
  • Keep water in your toilet bowl (unless driving).
  • Hold down your toilet flush pedal for at least 10 seconds every time you use it.
  • Dump your tanks every 3-5 days.
  • Flush your tanks very well every 3-5 dumps.
  • Prevent as much grease and food debris as possible from getting in your gray/galley tanks.
  • Don't clean your toilet, sinks, dishes or showers with chemical or antibacterial cleaners.
  • Deep clean your black tank twice per year and your gray tank after each dry camping/boondocking trip.
  • Store your RV with a full black tank of water and a bacteria and enzyme solution if there is no concern of freezing.



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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