If you own an RV, you know how important it is to maintain your tank system. Over the years we have come across a lot of products that promise to help. One that has genuinely stood the test of time is the Flush King. We have been using it for over 15 years and it has never let us down.
The Flush King is a simple tool that attaches directly to your sewer hose outlet. Its job is to let you back flush your tanks from the bottom up, so waste and debris actually get cleared out of your black and gray tanks instead of just mostly draining.
Why back flushing works better than gravity
The normal way of emptying tanks relies on gravity, the drain valves, and the sewer hose. It works, in the sense that the tank empties. What it does not do is clean.
Solids settle. Paper collects around the valve. Residue builds on the tank walls and inside the pipes, and none of that leaves just because liquid flowed past it. Over a few seasons you get the three classic symptoms: slow draining, a tank sensor that permanently reads full, and an odor you cannot track down.
Back flushing pushes water up from the drain valve instead of letting it fall out. That breaks up what has settled and carries it out with the flow. It cleans the plumbing rather than just emptying it.
What it does well
Clears clogs in the drain pipes. Blockages are usually somewhere you cannot see or reach. Pushing water backward through the line gets at them from the side that matters.
Works with any plumbing layout. Tanks sit at different heights and the plumbing bends in ways that vary by rig. Back flushing does not care. It fills and flushes regardless of the configuration.
Attaches in seconds. It connects to the sewer hose outlet with a secure fit. No tools, no setup, no mess.
Keeps tanks cleaner between dumps. Less residue means fewer odors, better draining, and tank sensors that keep telling you the truth.
Saves you time. A few extra minutes at the dump station beats an afternoon chasing down why the black tank will not empty.
How we use it
- Dump the black tank the normal way first and let it drain fully
- Attach the Flush King between the drain valve and the sewer hose
- Connect a hose to the flush inlet and open the water
- Fill the tank partway, then open the valve and let it rip
- Repeat until what comes through the clear section runs clean
- Do the gray tank last, so the soapy water rinses the hose on the way out
That last step matters more than people expect. Always end on gray.
One rule worth stating plainly: use a dedicated hose for this, never the one you drink from, and store it separately.
A must-have for every RV owner
We have tried a lot of products for keeping RV plumbing in shape, and the Flush King is one of the most reliable and efficient tools we have used. With 15 years of use and countless cleanings behind it, we can say it will become a permanent part of your routine.
Do not wait until clogs or odors become the problem. Keep the tanks clean and the problem never starts.
If the tank is already past that point
Sometimes a tank has gone too long and back flushing alone will not recover it, or a sensor stays stuck no matter what you do. That is fixable, but it is a different job.
We handle tank, valve, and plumbing repairs throughout Southeast Michigan, at your driveway, campground, or storage lot.
Call or text 248-517-5165, or check whether your address is in our service area.