[DutchmenSport]

Thanks for some clarification.

My first thought, as stated above, a poop pyramid has formed in the bottom of the tank. More than likely, it was already started by the previous owner, but over time, it's built up even more. Also, as stated above, using a toilet wand down will help break it up, and then add some enzyme eater type pipe cleaner into the tank and let it sit for a few days to help break up the build up.

The second thought I had was, you could have a leak in your toilet. But you'd need two leaks happening at the same time.

The first would be, the water is not shutting off completely at the toilet and you are not noticing it. If you are connected with a garden hose you'll never hear anything. However, if you were pumping water from your fresh water tank with the on-board water pump, you'd hear the pump running every time it turned on to keep pumping leaking water. It takes only about 2 ounces of water to turn the water pump on and off because there is no pressure tank.

But if this is the case, then you'd also have to have a leaking seal in the bottom of the toilet bowl allowing the running water to flow on down into the holding tank. So in order to blow this theory out, the simple question is, does your toilet hold water or does it go dry between flushes? If it goes dry, the seal is leaking. If it keeps some water in the bottom, it's not leaking and, if not leaking, the bowl would fill up completely before the tank would.

So, if this is the case, then that leaves the poop pyramid syndrome as the cause.