Incorrect reading of the water tanks in most cases is due to build up of scum and dirt in the water tanks.
This video will help you find out the root cause of the fault.
We recommend to clean your water tanks regularly.
Rust on the dippers? - leave them in the solution with the RV tank cleaner for a couple of days.
Images: Before and after. Rusty dipper has been cleaned with the RV tank cleaner.
Our Customer Service experiment:
"I have put one of "faulty" original dippers in a jug of RV tank cleaner. after two days, you can see the difference between the one untouched vs the one in the RV tank cleaning solution. The original dipper is working perfectly.
As tanks can be left stationary for any length of time, regular cleaning is required as part of the vehicle maintenance and is just as important as checking tyre pressures. Tanks need to be regularly cleaned to stop bacteria and algae growing inside the tanks. Tanks are like the shower walls at home, that get a buildup of scale and scum. I personally clean my own tanks every 3-6 months with a tank cleaner and use a twin filter system to fill the tanks from town water as I don't know what impurities are in tap water." - Stewart / Customer Service