hi the smelly job!
You will need the right chemical for which the site allows !! perhaps member could put the one they use and price per litre..
put some chemical in the toilet measured amount with a drop off water! in the spout thetford say..
[DO NOT pour Aqua Kem into the holding tank through the blade hole: always add it via the pouring spout. ]
then to empty after !!!
Take to chemical waste area! find this when you arrive on site!
mind you dont lose your cap down the waste hole ! empty and wash out with water a couple off times add the chemical again has before..!!1
if winter and laying up keep empty
Ray
ray