[jimcol]

Here it goes and probably not the answer you want. Those tank gauges aren't very reliable. Many of us don't use them at all other than for entertainment. As you get to know your rig you learn signs of when the tanks need dump. The toilet will burp, and the sink or shower will back up. Over time you just know when they need dumped before the back up. Some on here have upgraded to more reliable gauges, I have just never seen the need.