What's in our waste tanks after FIVE years on the road?!?!? More than we thought!

Our Dump / Flush Process

While at a full-hookup location, we typically leave our front grey (shower, sink, washer) open with a P-trap in the sewer hose (this will change going forward – see below). We keep the kitchen grey closed and dump it periodically or when the kitchen sink backs up.

STEP 1 (Open Flush): When it's time to dump the black, we start with a running flush. We hook up the black tank flush (separate hose), open the black tank, turn on the flush hose, and let it run for about 15-20 minutes or until we see mostly clean water.
NOTE: During this flush, I also reset the water meter on the flush line to see how many gallons we used during that time to get an idea of the flow rate for the next step.
NOTE: If we have buildup in the poop tube (3″ line from the toilet to the tank), this is when I clean that with a long-handled brush.

STEP 2 (Closed Flush): Then, I reset the water meter (on the flush line), close the black tank, and set a timer (usually about 10 minutes but also based on the flow rate measured during Step 1) to let the flush fill the black tank. DO NOT SNOOZE this timer! If you over-fill the black tank, it can be a VERY BAD DAY!

STEP 3 (Dump Dry): (When the timer goes off, I open the black tank again and turn OFF the flush line to let it empty completely, which usually takes about 10 minutes (another timer).

STEP 4 (Open Flush): With the black tank still open, I turn the flush line back on and watch the output. This usually yields more solids (toilet paper and 💩) as the flush sprays the empty tank.

REPEAT STEPS 2, 3, 4: I repeat steps 2, 3, and 4 until I see mostly clean water coming out.

STEP 5 (Happy Camper): We then treat our black tank using Happy Camper (see Happy Camper Below)

Tank Sensors

The bottom line on the tank sensors built into the tanks is that they are useless and stop working after a couple of months of use. We never even look at them. We know we need to dump a tank when:

Black Tank: If we start to smell black tank odors or the toilet burps (seems to make a bubble) when flushing, we dump it.

Front Grey (shower, washer, etc.): If water starts to back up into the shower drain, it's time to dump.

Rear Grey (kitchen): When the water backs up into the kitchen sink, it's time to dump.

Kleen Tank

While at the Grand Design National Rally recently, we ran into some old friends whom we met at our very first rally back in 2018, Wendy and Joe. Since we'd last met, they started a Kleen Tank business (franchise) in Michigan and were performing tank cleaning services and the Rally. We figured it was the perfect time to try this out and see what was still in our tanks after five years on the road!

The process is fairly straightforward. They have a routable (stiff) hose with a special spray tip connected to a small pressure washer. They insert this up into the tanks via the dump valve to spray pressurized water around the tank to loosen up the buildup and flush it out.

We were quite surprised at how much mold broke loose in our grey tanks! Clearly, we can do a better job at maintaining those! Luckily, it seemed that our black tank process is doing well as we got less out of those than we did grey.

Happy Camper

Joe and Wendy, as well as Kleen Tank in general, do not recommend using Happy Camper as a tank treatment. This is due to the result they've experienced firsthand while cleaning tanks. In their experience, they've seen many Happy Camper users get a very thick sludge buildup in their tanks (see the video).

However, they saw none of that with ours, and we've been using Happy Camper for five years full-time, and we've been very happy with it. It eliminates odors and breaks down solids very effectively! So, what's the difference?

We believe it's both application and maintenance. Happy Camper needs to be sprinkled into a gallon of water and mixed well BEFORE putting it into the tank. It is not meant to be just scooped in and flushed. We do this by filling our toilet bowl (1 gallon) while simultaneously sprinkling in a scoop of Happy Camper. The force of the water filling the bowl provides plenty of agitation to mix the powder. Then, just flush the mixture into the tank, and add two more gallons. Water is your friend in the black tank!

Proper application combined with proper flushing (see above) should yield good results with Happy Camper.

Going Forward

Kleen tank recommends keeping a 32-ounce bottle (they supply one with treatment); they recommend a mixture of 2 ounces of softener (Calgon), 10 ounces of PineSol, and the rest of it is water. Keep this mixture on hand and use it to treat your tanks after flushing and dumping.

They recommend this for both black and grey. However, we tried this mix in our black tank, and the odor peaked in the black tank faster than with Happy Camper. Granted, this was just one test, but we applied Happy Camper, and the odor disappeared.

Our plan moving forward is to keep using Happy Camper in our black tanks and to use the new mixture in our grey tanks – particularly on travel days to slosh the mixture around to clean it.

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