Lets talk poop! Keeping tanks clean and sensors working is always a popular RV discussion. It’s been a problem for all of us. Why does my black tank sensor always read 1/3? Why won’t my tank drain? These are daily questions on RV forums and Facebook.
And for good reason. The sensor systems installed on most RV’s don’t work very well…
And when the tanks get a little scummy, they don’t work at all.
Ours quit reading less than a season in. My response (6 years ago) was to purchase and install a SeeLevel 709 sensor system (affiliate link)
And guess what?
After a couple years, the SeeLevel gray tank sensor stuck on 100%!
The black tank sensor was kinda flaky, but mostly read OK. Interestingly, our rig had a factory installed black tank sprayer, which I used most of the time.
The SeeLevel system is highly recommended and will be a subject of a future blog post (once I find the pictures!) but for now…
Calls to SeeLevel indicated that our gray tank had enough of a coating on the inside to kill the signal from SeeLevel’s external signals.
After some searching, I came across the “Tornado” sprayers by Camco. The part number is 40126, and they are available at Amazon (affiliate link).
These spayers ROTATE! 
The photo above shows the sprayer attached to a garden hose. It creates quite the spray!
The kit comes with everything needed to install it, except for a tube of silicone sealer. I decided to use 2 sprayers in each tank, as ours are long and flatish. I purchased a couple of Tee fittings, so I ended up with an inlet for the black tank and an inlet for the gray tank, each with 2 sprayers.
To get access in our Monaco, I had to remove the white cover that made the wet bay look nice. Under the cover, it looked like this!
Installation was simple, drill a hole, gob around it with silicone, insert the sprayer, and run in 4 (included) self-tapping screws
and attached the hose.
I used the existing black tank sprayer inlet for one inlet (I sealed off the original black tank sprayer, it didn’t work well anyway) and used a Valterra RV water inlet fitting to add the second sprayer connection (affiliate link).
And then I put the original white cover back on over that mess of pipes and hoses.
For a future blog post, at the same time I replaced the original useless “outdoor shower” with a narrow base chrome bar faucet, and put an adapter on it so I can attach a hose. That lets me wash my car with hot water, and connect a short hose and use hot water to run my tank sprayers.
It took about 6 weeks of weekly dumps, spraying everytime, to get my gray tank sensor to work again. I continue to run the sprayers every time I dump, and the sensors on my tanks work perfectly.