Les, Over asked:
Would a siphon in free fall be the same as the siphon is zero gravity? Is it a good measure?”
Dominic - Yes, it is. When you're in free fall, you're essentially in zero gravity because all parts of your spacecraft are falling at the same speed towards the Earth and normally, you feel gravity because "I'm feeling an attraction towards the Earth and I'm being stopped from falling towards the Earth by the chair underneath me and so the chair has to push me up to stop me from falling towards the Earth".