How to measure Blended Soup?

 

How do you measure blended soups?  Do you eat only 2 ounces like a meal or since its liquid are you supposed to have 8 ounces.  

I blended a soup and added water ( to keep it thin)  but not sure how much to have?   

My plan calls for 2-4 ounces of anything that's not a clear. 

I just wanted to add that I do drink protein shakes and don't pay that much attention to how many ounces because I need the protein. I am able to get down an entire shake (8 or so ounces) over an hour or so.