Tuesday, November 28, 2023


Holy crap! Poo pyramid in my black tank!

Sh** happens! Poop pyramids happen! Especially if you dry camp, like I do, and are a full-time RVer, like I am.

I’ve been on the road long enough to know better, but… My RV black tank just got graded an “F.” As in: I flunked flushing!

Wow! How did this happen?

Well, I bought my fancy one-year-old “used” 28-foot-motorhome eight months ago and within a few days, the black and gray tank sensors didn’t work. They never worked on my other two (used) RVs, either.

My “trusty” salesman told me to use the back-washing system and they would work. That is a nice option, but it was just another lie.

I figured I usually have to dump every two weeks if I am careful with the gray, just like what I have been doing for the past eight years.

But, more than a month ago, a smell started wafting up from my toilet after I flushed. Yet another thing wrong—I’ll fix it when I can get to it, I reasoned. I kept on back-washing when I dumped.

When I went to my RV manufacturer’s rally in October in Elkhart, Ind., I saw my solution: A Kleen Tank booth. I instantly plunked down the $250 to get my black and gray tanks flushed. (Rally price: $250. Normal price: $275.)

Tim Branstiter, a traveling Kleen Tank dealer, gave my black tank an F. And my gray tank got a C. (Not as bad, but mold. Double yuck.)

The culprit? I don’t use enough water when flushing!

Hey, wait a minute! I flush! And I figured by gathering most of my gray water in my sink basin and pouring it down the toilet I was doing what I needed. Wrong! In my defense, I do this because my freshwater tankcapacity is only 27 gallons, my gray water tank is only 23 gallons and my black tank is 35 gallons. It’s harder than I thought to dry camp with.

But my problem apparently just kept on “accumulating.”

NEWS ALERT! Most of us are not putting enough water in our black and gray tanks. I will explain later.

To compound my embarrassment, I was the first person at the rally to have my tanks cleaned, so a crowd of fellow RVers gathered ’round with their folding chairs and beers to watch. It’s what “passes” for entertainment in the RV crowd.

Tim, of Kleen Tank, told me I had a “mound.” I had heard about those. You can guess what the “mound” is made of. My “report card” said my initial flow was bad, I had an “obstruction” and the tank odor was “bad.”

Tim said he was “98 percent sure” my smell would evaporate. And it did. Tim said he was pretty sure my sensors would start working. The gray tank indicator works a bit better. The black not at all. He said to keep using his tank formula (more on that later) and they still might start completely working.

Logo for Kleen Tank.
Thomas Scott’s operation out of Red Bay, Alabama.

There are other professional RV tank cleaning companies out there. If you have ever been to Quartzsite, AZ, I am sure you have seen ads for the “RV Proctologist.” I also talked to an independent tank cleaner in Red Bay, AL, and he told me his process.

But Kleen Tank probably has the most dealers of any outfits out there (46, two in Canada) and has been perfecting its process for 11 years.

Like other professional RV tank cleaners, they used a process called hydro jetting—they use 1,500 PSI pressure through their design of nozzles. Kleen Tank uses only friction to get tanks clean—no chemicals.

Thomas Scott, of Tri-State RV Tank Cleaning in Red Bay, says, “My specialty is a higher volume of water. I use about 2,500 PSI. Other guys use 3 gallons a minute; I put in 8 gallons a minute.”

Wherever you get your tanks cleaned, professionals agree you need to do it at least once a year.

What to do each time you empty your black tank to prevent poo pyramids

  1. Every time you empty your tank, you should put 3 to 5 gallons of water down both toilet and sink. I have never put water down my sink after dumping so wow—this was news to me! (I faithfully put in two gallons each time I emptied the black and, apparently, that was not enough.)
  2. STOP using tank additives. Really. Kleen Tank says that is your second biggest mistake. “Those chemicals and enzymes you’re using create a sludge—or thick, pancake-like batter—that makes it impossible to get waste out and tanks clean,” its literature says. And that stuff gunks up your sensors, too. Wow, there’s a headline. How much have I invested in those packets over the past eight years? (FYI, Thomas Scott disagrees here. He thinks Happy Camper is a good product. Also, “The cleanest tanks I have seen use lots of water and Dawn dish detergent,” Thomas said.)
  3. So, what does Kleen Tank suggest you use instead? A mixture of water, Pine-Sol and Calgon bath pearls, beads or liquid. This is interesting that Kleen Tank doesn’t try to sell you its own formula. A pint of the stuff comes with your cleaning. I’ll tell you their recipe at the end of the story. Again, Thomas doesn’t agree with this formula, so…
  4. Keep that water flowing when you “go.” “Start with a half bowlful of water, relieve yourself as needed, flush it down, fill the toilet bowl at least halfway, flush that down,” the Kleen Tank literature says.
  5. Don’t empty your tanks before they are 75 percent full. You want the swirl or vortex to help clean your tanks.
  6. If you have an internal sprayer, use it when emptying the black tanks.
  7. Don’t equalize the gray back into the black tank because you could cross-contaminate. (My RV salesman had offered that as a solution to my smallish gray tank. Aaaaah!)
  8. When parked and hooked to a sewer, do not keep your black tank valve open. That’s when the sewer flies hit. (Luckily, I have never encountered these awful creatures. Have you?)

RV tank cleaning myths

  • RV toilet paper. Tim says if you use enough water, you can use any kind of toilet paper you want. (Is it TMI if I tell you I have never put toilet paper down any of my black tanks?)
  • Tank rinsers—they help but just aren’t up to the task.
  • Ice in the tanks will break things up—nope.
  • Dawn and other dish detergents in your black tank—nope. (As opposed to what Thomas Scott said.)
  • Borax—nope.
  • Laundry detergent and pods—nope.

Which RVs have the most holding tank problems?

  • Your RV is three or more years old
  • You are the second or third owner
  • If used, your RV may have sat on a dealer’s lot
  • Previous owner was negligent or inexperienced (or maybe like me, uneducated in this regard?)
  • RV was a rental unit
  • Used full-time or in harsh conditions
  • Communal bathroom use

Kleen Tank’s recipe

Using an empty and clean one-gallon plastic bottle or jug, add 8 ounces of Calgon bath pearls, beads or liquid to the bottle. (Do not use a bottle of Calgon water softener like I bought and had to throw away.) Measure 40 ounces of Pine-Sol or similar product into the bottle. Slowly fill with water, waiting for the suds to “die down” before adding more water.

Add solution to both tanks every time after emptying:

  • Dispense 4 ounces each into black and gray tanks that are less than 45 gallons in capacity.
  • Dispense 8 ounces into each tank that has more than 45 gallons in capacity.

Well, I guess I will be using more water, trying to find more water and dumping more as I travel down life’s highway. The great thing is—I am not too old to learn.



Jan Steele
Jan Steele
Former newspaper editor Jan Steele started her career in third grade as a school correspondent for her local newspaper and has been writing for publication ever since, including a 30-year-stint at the Herald-News in Joliet, IL. She decided in fourth grade she wanted to hit the road as soon as she could—and retired eight years ago to RV full-time.



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Roger Eide (@guest_258697)
29 days ago

My TT is a 2016 and the tank sensors still work. I have never tried that recipe but will in the future. I usually add 8-10 gallons of water to my black tank before using. I dump 2 pails of water right down the toilet. I also dump 2-3 pails of water down the toilet when flushing the tank in addition to using the black tank flush. I have not added water to my gray tanks but will be from now on. I have been rving for 50 years and in TT for 30 or more and luckily have never had the dreaded pyramid.

Rod (@guest_257989)
1 month ago

I use a lot of water. Put a rubber water hose from outside through the window into the toilet. Turn on the water and let it run. Load the tank with water, load the toilet with water, flush, load until the water is clear coming from the black tank. Leave a little water in the tanks until you get to another place where you have hook-ups. Repeat the cycle. It works.

Robert (@guest_257934)
1 month ago

After attending a manufacturer based rally at Elkhart we tried the Kleen Tank recipe and double flushing for several months. Sensor function got worse.🙁
Tried Boraxo and Dawn. Boraxo stops ants but had no effect on sensor function.🙁
Tried lots of water.🙁 Less expensive but odors returned.
Now re-evaluating Happy Camper.🤔
What works for us: Double flush🚽🚽. Add ~5 gallons of water per tank after dumping. Happy Camper reduces/eliminates grey tank odor. Add enough water etc to tanks so >2/3 then dump when leaving a campground. 100 miles of sloshing loosens a lot of 💩. Dump again on arrival if black tank flush is convenient.

Jim Godfrey (@guest_257919)
1 month ago

Jan: I enjoyed reading your well written article. But I have to admit I get the feeling that the Kleen Tank company is kind of capitalizing on the “EWWW” factor when it comes to black tanks. I now have the SeeLevel system with external probes. It works flawlessly. However my last RV, which I owned for 15 years, had the standard “in tank” probe system. In those 15 years we also never had a problem with false readings. I believe the reason for this good fortune is simple. Use more water when flushing solids, and use the black tank flush often. Nobody likes to think about what goes on in our tanks, but even after a thorough “Kleening”, you are only one poop away from a smelly tank.

Split Shaft (@guest_257765)
1 month ago

My thoughts are those undercounter sink vents are the cause of most foul holding tank odors in RV’s. I have no clue when the holding tanks are vented thorough the roof, why those undercounter vents should release tank odors when waste water is added to the tank or the tank is dumped, but they do. I have removed them, inspected them, and found nothing wrong. What gives?

Robert S (@guest_257734)
1 month ago

Well written article, have not had your experience, but have been using the packets that came with the new rv. Now experiencing the smell and having trouble getting clear water at the dump station, will definitely try your solution.

Bob P (@guest_257714)
1 month ago

NEVER FLUSH FACIAL TISSUE DOWN THE TOILET, SIL had a recent surgery with an open draining wound he had to clean several times daily. He casually dropped Kleenex down the toilet after using it to clean the wound. Several days later he attempted to dump the black tank, it was plugged with undissolved tissues. He finally got the plug broke loose and drained the tank by drilling a small hole in the clear plastic elbow and putting a stiff wire through the hole and breaking loose the “dam”. Then plugged the little hole with epoxy.

Tom (@guest_257710)
1 month ago

I don’t see anyone mention using “The Wand” in black tanks. For me it’s part of routine maintenance, once a month or so when we are in the rig for the winter. Usually the sensors will work again for a while.
We use Happy Campers, works good, no stink.
If we start to get a little smell from the gray, then I put some HC in there too. We wipe food off of dishes with paper towels before washing, limiting the amount of food waste in gray tank really helps.

D. Gregory (@guest_257709)
1 month ago

Use Happy Camper. It just works; no smell and it breaks down solids to liquid. There are some incorrect statements in your article, as well. Possibly, Kleen Tank is drumming up business like the quick lube companies, who say to change oil every 3,000 miles; I won’t go there. Just follow the manufacturer’s recommendation.
After over 40 years of RV boondocking, I’ve never had solids stack up. A process that works:
*Fill the bowl with some water, about 2 inches
*Place a piece of RV toilet paper on top of the water
*Do your duty and flush. The paper will clean the bowl as it descends
When you dump black, pour a couple gallons of water down. Then use gray to flush the hose. Done!

Gary G (@guest_257699)
1 month ago

Check out the “Wandering Wagners” utube I’M SHAKING from Oct 2nd, 2023. They suggest using a product called Commando Tank Cleaner for messed up tanks. Just a suggestion.

Big RabbitMan (@guest_257698)
1 month ago

I have a 2976 FMC that I purchased in 1999. One of many things that I like about it is that the kitchen sink is plumbed into the black tank. This feature automatically adds water to the black tank and reduces the volume going into the gray tank. The Gray only receives water from the bathroom sink and shower. I also like to have the black with some fluid in it when traveling to slosh around while driving. I have never had an issue with either tank.

Steve Lane (@guest_257695)
1 month ago

Have used the Kleen Tank recipe for approx 6 months, it seems to work. We use plenty of water and add to the black tank with dish water. There’s only my wife and I, fill the gray tanks in 2 to 3 days, the black tank we never seem to fill. Most of our stays are 3 to 5 days in RV parks. I don’t travel with much in the tanks unless we’ve had a one night stay. Always add water to all tanks. Sensors still don’t read correctly. Have just learned to accept per what other RV’ers write, or tell us. RV is 2 1/2 years old.

Neal Davis (@guest_257673)
1 month ago

Great tutorial, Jan! Thank you! We have the remnants of a gallon of a natural tank cleaner that I add after each dumping. Once it is gone, then I’ll try your Calgon and Pinesol recipe. I also will more rigidly ONLY dump when black gets to 3/4. Thankfully, our tank sensors appear to work correctly. In our favor is our RV is 1 1/2 years of age and we are the original owners. I do hope to get our tanks professionally cleaned often, if not quite annually. Thank you!

Tim (@guest_257665)
1 month ago

2008 Cougar 291RLS, Happy Camper, Dawn, Borax has worked for years without issue. We use use Septic Safe TP, same that we use in our Stix & Brix system. Primarily camp in dispersed areas of Colorado & Wyoming

Skip (@guest_257649)
1 month ago

Wow! Thanks for the information. Very thorough and helpful.

Seann Fox (@guest_257633)
1 month ago

Are you sure this wasn’t written by Johnny Robot?

Janette Steele (@guest_257705)
1 month ago
Reply to  Seann Fox

On my goodness! Check my writer profile… I was a newspaper reporter and editor for 30 years! I can’t tell if you are trying to be mean or funny? Either way your comment was not appreciated!

Janette Steele (@guest_257726)
1 month ago
Reply to  Seann Fox

If I was a chat bot I think I would have a younger and sexier photo on my profile? 🙂

Larry (@guest_259019)
27 days ago
Reply to  Seann Fox

You might want to give some logical reason as to why you think that. Otherwise it is a useless statement and very rude towards the author.

Rock (@guest_257615)
1 month ago

My motorhome is 5 years old. We use it full time 5 months a year. I use Happy Camper. We use plenty of water when flushing. I have two 40 gallon black water tanks. I use the black water flush system with an inline flow meter continuously when dumping. I run the flushing until the water runs clear. I then use it to refill and dump the black water tanks a second time and then I use it to add 5 gallons of water to the tanks after dumping. My sensors work!

Linda Susan (@guest_257606)
1 month ago

Excellent article Jan! My sensors both worked initially after I had my tanks cleaned but the black tank sensor still doesn’t really work. Looking forward to more of your articles!!

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