You have two basic choices at a full-hookup campsite with a sewer.
1) Attach your sanicon to the camp ground waste pipe. It screws on threaded campground pipes.
This method requires you to run the macerator to empty the black tank as needed. The gray tank will drain on it's own as long as it's waste valve is left open. I personally like to keep both tank valves closed until ready to empty. I pump out the black tank first, then back-wash the gray into the black tank to flush it, then pump it out.
2) Use a stinky slinky to "gravity drain" as sewage is created.
With this method, there are two potentials for sewer gas getting inside your rig.
1) When flushing the toilet, a burst of sewer gas may come out.
2) The roof-top vent pipe vents the gas, some of it may get in through an open roof vent or window.
The kitchen sink, bathroom sink, and shower drain all have traps to prevent sewer gas from getting inside, so no worries there.
I mounted under our PC, a stinky slinky storage tube with Rhino waste tube inside. I carry one as a back-up for if the sanicon fails during a trip. The tube and slinky are out of sight mounted high, and are light weight.

