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Monday, November 21, 2011

How to dump and thoroughly clean your RV's black water tank

The RV Geeks demonstrate how to dump RV waste water holding tanks and thoroughly clean the black tank. Keeping your sewage tank super clean requires following a few simple procedures which will make it stay odor-free.

Many RVers think their black tank is clean when they just empty it and flush out the sewer hose with water from the grey tank. Even those RVers who use a black tank flush system often don't utilize the most important piece of equipment necessary to monitor the cleanliness of the black tank: a clear sewer elbow.


  1. I would have added that you should put some water into the tank after dumping so that the bottom is covered. This helps to keep the solids in liquid so they do not dry out and stick to the bottom.

  2. Very informative! We haven't purchased our motorhome yet but this is exactly the information we need when we hit the road the first time. THANK YOU!

  3. @Doug and Sheila — You're absolutely right about putting some water into the black tank after dumping. At 13:18 in the video, we did mention to put in a gallon of fresh water when you add the tank chemical. We only add one gallon so that we won't start filling the tank up any faster than necessary, but more water can definitely be used if desired, to be sure the bottom of the tank is covered. Instead, we prefer to simply use a little extra water during the first couple of flushes after dumping, especially if any of those flushes involve.... uh.... something more than #1. ;-)

  4. I like your ideals, I have not gone as far in some of the details that you have done, but now that I know, I will be doing more to check on the health of my black tank. Thanks for the pointers,.

  5. He dose say water in the tank at about:5:40 on the tape. Well done.

  6. Comment was made that the gray tank valve can be left open while hooked up to sewer. I was under the impression that you should always keep valves closed so sewer gas doesn't come back in. Correct me if I am wrong, please. Good info.


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