THE HORROR . .. .. . THE HORROR. ... . . THE HORROR

I gave up on the black tank sensors 11 years ago after our first month of camping. Like others have said experience will show how long one can go before dumping. I just look down the toilet toward the end of the known time period. But, NEVER, NEVER, use a flashlight that will fit through the hole in the toilet. Go, buy a bigger one if you have to.
Len R.