I'm curious. My doctor told me some of the saline used for the fill stays in the tubing.

Isn't there some sort of valve at the end of the tube where it connects to the inflatable band around the stomach, to keep the Fluid from flowing out of the band back into the tubing? Otherwise it would be possible to self-deflate your band if you ate too much or took too big a bite, right? I hope I am making sense.

I'm only asking because after a fill it seems like I have restriction for a few days and then it gradually seems to fade away, and I can eat too much again. Maybe it's just swelling.

Nothing like that - that I am aware of. The pressure really remains pretty constant. When you fill someone when the needle is in the port you kinda have to keep your thumb over the plunger of the syringe because it the pressure. If you let go of the plunger the Fluid from the band comes back into the syringe.

The tubing really doesn't hold very much. I can't even give you an estimate of how much it holds because many doc remove some of the slack during surgery. So some folks will have more tubing than others.