After having this rv since Oct 2016 we are now running into a pretty constant problem with the poop parade! It is now in both our throne rooms and we have already done More Water please and plunged and poked yet the parade returns. I noticed someone posted a blurb about a Chemical waste destroyer, have you tried it and did it work? Another blurb about Dawn did that work? Seems to be some type of ledge in both toilets. Any advice is appreciated. We tried hot water to dissolve it but it failed.