How do I sanitize my freshwater tank?

How do I clear a blocked holding tank?

There’s nothing worse than a blocked holding tank in your RV — except maybe a clogged up toilet (which is probably related to the tank problem)! But there’s hope — clogs and blockage, while dire, are pretty easy to take care of with a little knowledge and patience.
Toilet or tank?
First, you need to determine where the problem resides. Is it in the toilet in your RV’s bathroom (or pipes running down to the tank) or is it in the waste holding tank itself? So how do you find out where your problem is at?
If you see waste and/or water backing up into the toilet, the cause is almost always in the toilet. Yes, that seems obvious. But most toilet problems are caused by clogs or excessive amounts of toilet paper at the bottom of the toilet bowl or pipe, or in a pipe that drops from the bottom of the toilet into the tank,.
If there’s no waste, dirty water, or backup in the toilet, then your problem resides mainly in the waste holding tank. That doesn’t mean that toilet paper isn’t a part of the problem (as we mostly find in the toilet), but things aren’t likely to get as messy in your RV with a tank problem.
If it’s the toilet….
Actually, this is a pretty easy situation for the average RV owner to tackle. There’s one thing to remember here: Minimizing the amount of water you add to the situation is key until the clog is cleared. Clearing the clog is pretty easy if you have the right tools.
We use the Corky Beehive plunger with good results. Just be sure to open your black tank’s release pull first then gently push-push-push in the toilet until the clog goes down. After that? Buckets of hot water will help move the problem down into the tank.
If it’s the tank….
This can be a harder problem to solve, actually. If you don’t have a Kleen Tank authorized dealer near you, your options are limited. You may find some success with careful use of a backflush valve, such as the Valterra Flush King. It’s ability to move masses of clear, cleaning water up into the tank from the bottom can sometimes clear a stubborn clog or blockage.
Still can’t get that obstruction out? Give one of our Kleen Tank dealers a call! They are happy to come right out and help you out of your nasty situation.


Jim & Debbie Tome, Owners

Hi, we're Jim and Debbie Tome and we're the owners of Kleen Tank LLC, the nationally-recognized and largest professional network of RV tank cleaning service provider.

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, we've seen just about every situation there is with RV holding tanks and waste systems.

We hope you enjoy our question-and-answer articles; we try to post at least a couple per week and we've got a great library of them to cover just about every problem.

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