Thanks again folks, just come back from my weekend away and what a relief, pardon the pun, it was to have my Thetford Porta Potti Could eat and drink what I wanted through the day so didn't get dehydrated like I normally do and just a few steps across the tent to the spare pod in the night. I wrapped both layers separately in black bin liners, filled the top with 10 litres of fresh water and put the pink stuff in, then the bottom with 1 litre of water and the green stuff in and took it like that. Was a little heavy to lift out of car but not far to carry it. Managed to store my loo roll and wipes in the bowl as well while transporting it so didn't take up too much space Worked brilliantly and no horrible smells and was lots of fresh water left in the top tank when I came back so will put less in next time just for the weekend, I guess you guage how much after a bit of practice
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.