I have a Deer Run 250 that has 1/2" I.D. flexible lines for the permeate and concentrate outputs. I need to extend my permeate line so that I can reach some extra storage tanks. I'm using a 1/2" insert fitting to add the extra line. The insert fitting reduces the I.D. of the line a bit. I didn't measure it, but I can see the ID of the barbed end is a bit smaller than the NPT side.

Will the smaller ID on the permeate create a restriction that would have any kind of effect on the flow rates of the RO itself?