B.O. Plenty wrote:
Do you leave your black tank valve open when you are camped? This will allow the liquids to drain but keeps the solids in the tank and will cause the dreaded pyramid...Try using a Flush King at the sewer hose connection to help back flush it.
B.O.
B.O. thank you but we do close our black tank, that's why I don't understand how there could be a pyramid, but I'm willing to try anything at this point. Using the flush king would that back flush enough to go up the pipe to the toilet? Because that is where our blockage is most likely...