My current monitor system has stopped working, not just one but all the tanks. So I think it must be the board in the control unit. I could order a new one or I could look onto upgrading the system. I have found the SeeLevel RV gauges by Garnet Technologies system on the internet. Does anyone have any knowledge of this system? It provides the levels in percentages rather than the 1/3, 2/3, full that we have now. Any help would be useful to me.