Will....I keep my van at home so it is easier to prepare. Just before our first trip I quarter fill the aqua roll with a mild solution of water mixed with Milton baby bottle steralizer. (you can also use any supermarket brand, usually cheaper) I run this through the system and leave the system primed overnight. Then run through plenty of fresh water to flush the solution mix out.
Also, before I winter the van, I run a disinfectant solution into the waste water pipes, blocking off the exit route, so all the pipes are full of the solution up to the sink points. This helps to clear out food debris that may get stuck in the ribbed pipes. Again I leave it overnight and then flush through to clear any loosened deposits.
If you have a filter on your inlet it is always best to fit a new one at the start of the season.
Mal