[DutchmenSport]

Originally Posted by AZMont

I just a flow meter and clear dump fitting to fill the black tank and flush it several times when done with a trip. I keep filling and dumping until the water is clear. I typically put 35-40 gallons in each time via the power flush. This way there are no surprises when I open the cap later.

Rather than pumping 35-40 gallons into the black tank, why not use that Valterra, or a Flush King and back flush 35-40 gallons of gray water into the black tank, rinsing it out? Then as a final rinse, you can flush maybe.... a gallon ... of fresh water. I've been doing the back flush method absolutely every time I dump for over 20 years now, on 4 different campers.

I back flush at least, at a bare minimum, at least once. Sometimes 3 or more times, depending on how full the gray tank is. It saves water, it gives your gray water a second purpose, and it's very efficient at flushing out your black tank. In our environmentally conscious world we live in, it's a great way to re-purpose and save water.