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Judge · 10-25-2020, 10:47 AM

I agree that you experienced a damming situation from not flushing with enough water on a regular basis. Then when you were driving home, the "dam" broke. This could have happened for a two reasons: toilet flushing and black tank rinsing / flushing.

First, it surprises me how many people treat an RV toilet like a home toilet where one flush (1/2 to 1 gallon of water) gets the waste down stream.

Depending on the design of the black tank system (toilet to black tank location, plumbing, etc.) it can be exacerbated when not enough water is used for flushing. This is also why many people complain about their tank sensor being inaccurate.... debris ends up sticking to the sensors instead of being pushed to the bottom of the tank.

I flush a 1/2 bowl full of water for #1 and two bowl fulls for #2 to ensure the waste is going to the bottom of the tank. My coach has the toilet on the passenger side and the black tank and drain on the driver's side.

Then, after emptying the black tank I fill it full of water once to rinse it using the San-T-Flush port to further push out any remaining debris. I have a digital flow meter to know when I am close to having the black tank full before I open the drain again.

Just using the San-T-Flush to run some water through the tank won't get it done. Especially where you have low water pressure in some places. Filling the tank with water using the San-T-Flush allows 20 - 30 gallons of water to push any remaining debris out of the tank. Otherwise, you think the tank is empty but it is not and debris builds up over time. With the full tank rinse I can still see debris being removed from the tank.

Finally, we then add Calgon water softener and Dawn to the black tank with about 5 gallons of water.... the Calgon makes the water very slippery and hopefully coats the walls of the tank while we drive to minimize debris sticking to the sensors and other places inside the tank.

I know all the water conservationists will blast me for my misuse of water.... so feel free to do so if it makes you feel better. These rigs don't have a typical septic / sewer system and my method prevents odor, blockage and waste build-up and I am ok with that.