Temple of DOOM
Well, lesson learned..!
I believe that most RV repair places call it a "Temple of Doom". This "Temple of Doom" is created when we flush our toilets and there is not enough water accompanying the "solids". It falls into the holding tank and builds literally a "temple" of solid waste that be difficult to flush out.
A similar problem can occur if your black tank valve is not closed and the liquids are able to seep out leaving the solids behind to settle and solidify. There are many different ways to try and resolve the problem from flushing water backwards through a valve, to water hose down the toilet and many more in between.
Moral of the story is don't be cheap on the water when flushing the brown down, it might mean a trip to the sani-dump or and draining your black tank more often but trust me it is worth the headache not too.
Glen & Robyn (A.K.A. Puff & Crickit) Full Timers..
2006 F350 6.0 with 3.73 gears, 4X4, Extra-Cab Long Box, Oil/Tranny/P.S. Coolers. Coolant filter. SCT Livewire.
2011 Cedar Creek 36RE, Auto levelers + too much to list..!