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Padlin's avatar
Padlin
Explorer
Aug 05, 2014

Holding Tank Usage

At the end of a weekends use the black tank is only partially filled, maybe 1/4. If the next outing is a couple weeks away, does one dump the lightly used tank or let it sit till after the following trip?

How long do you wait to dump your black tank if lightly used?

18 Replies

  • Sandia Man wrote:
    ...any longer than that and we just dump somewhere on the way home...

    Behind Walmart, in an isolated storm drain, on an empty lot, isolated pasture, etc??? :) :) :) just kidding!!!
  • Pretty common occurrence as it's difficult to fill a black tank in just a couple of days. The camping situation dictates when we dump the black tank when not filled, most times we don't as we predominately drycamp and boondock where dump stations are nowhere to be found.

    If we are planning to camp with dump station or FHU in a week or two we will wait until then, any longer than that and we just dump somewhere on the way home. We always dump when we have FHU when camping regardless of how filled the tanks are, great opportunity to get black tank properly flushed/rinsed out.

    On a few occasions we had intentions of camping within a couple of weeks and plans fell through at the last moment, went nearly a month and didn't have any issues (odors) other than having to hitch up TT and dump at a location a few minutes from our home. That is why for the most part we dump before getting home where we store our rig, it's just easier in the long run.
  • I have both left it for dumping later and ran bathroom lavatory (drains to black tank) to get 1/2 to 2/3 full. We have a sewer clean out at home I can dump/rinse tanks into but it requires a little jockeying around yard to get MH positioned. I'd like to get a macerator or sewer solution to make dumping at home easier.

    We also will use MH facilities at home when working out in yard or shop. A few trips I've actually swung around by dump station upon arriving at campground to dump before setting up site.
  • This is a chronic consideration (unless you can dump where you park for free. If you have to pay to dump, it becomes a serious question.

    Here is from my experience both in boats and RVs.
    If it is cool and your tank treatment works well, you can hold off on dumping (pumping out)until the level is the issue. If those conditions aren't met, you will not want to leave the tank to brew for a week or more. You will know you should have done the dump and rinse when you get close.

    Dumping a tank that is well less than full can leave a lot of solids behind. If you have to do this, run water in until you have a good level, then dump. It is even better If you can get the tank level up and take it for a ride. That will stir things up so the dump goes better.

    Matt
  • I only dump when full, if I have been dry camping and only have a mostly empty tank and plan to go camping again in the next few weeks I just leave it until my next trip.

    Most times my next trip will be a Full hookup site and I will dump when needed. I have used this method for many many years, sometimes for as long as 6 weeks with out any problems.
  • I would dump. What if for some unknown reason you do not use the RV in the next few weeks? What if you do not use it until next season? It has happened. I wish you the best.

    Ray
  • I fill the tank to about 2/3 full and dump, but if I haven't flushed the tank with my Tornado for a while, I just dump then flush it clean.

    That said, our previous trip was dry camping and I didn't dump until the first stop on the next trip, about 2-3 weeks later. Worked out fine.
  • I would dump it! I always try and go home with clean tanks. Then my next trip, I'm starting with empty tanks! After watching the video on here with the guy doing an experiment on draining tanks, I don't buy into the deal where should only dump a near full tank. The rinse is the most important part. My 2 cents! worth perhaps a penny or less!

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