Since we’re sometimes pretty serious boondockers (that’s camping without hook-ups for you RV newbies), we want to know the exact levels in all of our holding tanks – fresh water, gray water and black water – and our propane level too.
We have a fresh water capacity of 105 gallons, 65 gray and 45 black. The limiting factor for boondocking is always the gray tank. We can easily spend 7 days out in the desert, with both of us showering every day, cooking every meal on board, doing dishes etc. If we know we’re going to want to stay in one spot longer, we can make it up to 10 days by being REALLY frugal with water. When the gray tank is full, we always have about 1/4 tank of fresh water left, and the black tank usually takes about two weeks to fill.
A key part of knowing how long you can stay in one place without hook-ups is knowing the levels in your fresh, black and gray tanks. This video will show you how we calibrate our tank monitors so we always know where the levels are. Tank monitors vary by make and model, but this will give you an idea about how we calibrate our Newmar monitors.
This is not something that needs to be done on a regular basis. We calibrated our tank monitors shortly after purchasing our motorhome, and have never needed to touch them since.