rv toilets are very basic and easy to maintain,, obviously you are not doing something right! before using it you should run some water into the toilet, do your business and run the water! the matter and paper should fall straight down,, unless something is blcoking the hole,, there is no need to rotor rooter anytime!!!!! if it clogs it could be something stuck in the pipe or the pipe could have been misaligned someway.... use a flash light and look straight down the pipe with the flush handles pulled back!! you should be able to see the bottom of the holding tank,, or a layer of matter floating there!! dump all the matter proper and use a hose with running water to completely clean out the holding,,, see what happens then,, if it is a newer 5th wheeler, the gray and black tanks could be hooked together via a t or y connection,, check that this is still connected properly!! search RV sites on the net,, they have some real good help there from many people who have years experience!!