We’ve seen more and more competitors of Kleen Tank recently start their business. At least one that claims that they can sanitize your RV’s waste holding tanks. Is this a good idea and does it need to be done?


As you know, your RV’s holding tanks are essentially large, plastic boxes that either collect waste (your black and gray tanks) or contain potable water for use in your shower, sinks, and even toilet when you choose to use your onboard water tank rather than your RV park’s water supply.

Varying in size and location, RV water tanks are usually made of ABS or polyethylene plastic. There is one for fresh water, typically one or more gray water (waste from sinks and showers) and usually one or two for your black water (waste water from an RV toilet).

Your fresh water tank is made from food-grade, FDA-approved, BPA-free, rotationally-molded polyethylene that meets ANSI NSF 61 manufacturing requirements. Polyethylene potable RV water tanks offer dependability, a long service life, and great defense against cracks, rust, and corrosion.


Waste holding tanks (gray and black) collect waste from inside your RV. Anything that gets flushed down the toilet, rinsed down the shower drain, or that goes down sink drains inside your RV ends up in your waste tanks. They are part of your RV’s holding tank system.

Waste in the tanks is measured by tank sensors that determine the volume of waste and water inside the tank. When your tank sensors show the waste tanks as full, that’s your cue to empty them by pulling or activating your waste tank gate valve pulls. Waste travels out of the tanks, through waste pipes, and into your flexible sewer hose, into the ground waste handling system at your RV park, resort, or campground.

Freshwater tanks, which contain potable water for use inside the RV, use a small pump to circulate water in your water-supply plumbing system. Typically, water directly from the freshwater tank provides the “cold” water, while hot water is provided by pumping water through a water heater and then into the “hot” water pipes.


First, let’s talk about what should be sanitized and why. Sanitizing is done to remove and control molds and mildews in your freshwater tank.

Your freshwater tank and connecting pipes should be sanitized periodically with a sanitizing solution, such as a mild water and bleach mixture. Water and bleach is pumped into the freshwater tank, the pump is used to circulate the water-bleach mixture through the plumbing system, and the taps (shower and sink faucets) are opened to sanitize those as well.

The correct ratio of bleach to water is 1/4 cup of bleach for every 15 gallons of capacity in your freshwater tank. For example, a 60 gallon tank would use one cup (8 ounces) of bleach during the sanitation process.

Now, what about your waste holding tanks? Can or should they be sanitized as well?

Well, no, there’s no way to sanitize your black or gray tanks, and there’s no reason too. It be extremely difficult — if not impossible — to do so (it would require extremely high heat, extreme pressure, and/or incredibly caustic, antibacterial and antiviral chemicals.

In fact, even if you could sanitize your RV’s waste holding tanks, the first time they are exposed to waste (either human, food-based, or otherwise), they would be contaminated again and thus, unsanitary.


If an RV tank cleaner suggests or states that waste tank sanitation is one of their services (and is necessary),choose another service provider as, in our opinion, they are trying to sell you an impossible — and unnecessary — service.

If you have any questions about how to care for your RV’s holding tanks and waste handling system, give Kleen Tank — or any of our Authorized Dealers — call. We’re always available to answer questions by calling us at 844-KLEENME (844-553-3663).

Jim Tome, Owner

Jim Tome, Owner

Hi, I'm Jim Tome and, along with my wife, Debbie, the owners of Kleen Tank LLC, the national leader in RV holding tank cleaning service. We've been RVers like you since 2004 and have traveled all over the U.S. in our Airstream travel trailer. We started the business about twelve years ago and have cleaned tens of thousands holding tanks in thousands of RVs. From tiny weekend travel trailers to monstrous fifth wheels to luxurious motorhomes, I've seen just about every situation there is with RV holding tanks and waste systems. I hope you enjoy our articles; I try to post at least one per week and we've got a great library of them to cover just about every problem. Enjoy!


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