I just relate your experience to my my own experience with Bathmate pumps. I think it's a difference in Bathmate pumps (hydro-pumping) and Air-pumps. That's the reson I give you this clear information, that you need to keep at it in a relentless way.
I got practically non expansion when I started to pump with Bathmate. And now the hydromax 5 is almost to small (girthwise).
and is your routine the exact same as mine? Girth program (SRT 5x5x3) using a hydromax 5? Is it the hydromax 5 what youve used throughout any recent gains?
Follow the link to learn more about: Girth program (SRT 5x5x3).