Lots of motorhomes hold water in the bottom of the tank when drained. We used to (we have a caravan now not a motorhome) put cleaning solution in, part fill the tank with warm water, drive round to stir everything about and then empty the tank.
------------- Jean
Sometimes a little rain must fall before you reach a rainbow.
The work will wait while you show the child the rainbow, but the rainbow won't wait while you finish the work.
If you know any plumbers or heating engineers ask if they will give you a condensate trap out of a combi boiler when they are fitting a replacement.
They are small and quite slim. This makes them easy to fit into the pipe work under the sink.
Also if you can access the pipe work that goes into the waste holding tank you can normally bend the flexi pipe to form a makeshift U bend.
Teaspoon of bicarbonate of soda down the plug, followed by a slosh of white vinegar. Cheap & effective against smells, and the frothing is good fun. Finish with a kettle of hot water.
Drop 6 or 8 ltrs of cheap cola NOT diet or sugar free down the sinks making sure the waste is closed.
Go for a drive for 10 mins or so then drain. Its normally all the crud in the waste tank that smells. Also put plugs in when travelling.
------------- April Peak District Beech Croft Farm
May Peak District Duke of York
May Holland Delfse Hout
June Cotton Arms Nantwich
july/aug Cornwall Pentewan Sands
And quite a few local weekenders