Waste tank level Gauge

[themorganjane]

My boat has a Waste tank Gauge indicator located on the electrical panel. The rocker switch next to it has 3 positions. It will rock down and stay there, it will rock to the middle and stay there and then it will rock upward and stay there momentarily as long as you hold your finger on it. once released it returns to the middle position. What does each position supposed to represent? I am having troubles getting any readings so I first want to understand how it is supposed to work. Thanks for the time guys.

 

[Moose]

I'm not sure about yours, but when my indicator says 1/2, I'll wait about 2 weeks(depending upon usage of course) and then it's time to pump out. Mine never says "full".