Thanks for response, but,...
unfortunately I don't seem to have volume in my drop down list, (I tried to change the family category just in case they had different options in the category parameters, I tried it as a Generic Model and Specialty Equipment too adn volume does not seem to shown up) this is the closest I can get to it and it does not work; I tried it in case there was a language interpretation chance but not so. I also tried to use the GB Volumen and make that Litres and tag that as well but it does not show up and tbh I don't know what GB Volumen means as it was the only thing that looked anything like a volume. It seems either Revit Lt does not have it or I need to add them prior to getting to this point??


I did try and set it up as different tags too but it does not show
I also tried this process but that did not work either:

I attached the tank but that wont help as its just a cylinder model