MY homemade pump seal

I used a gardeners pad to make my padding on my homemade pump. It seems like it sizes down the base of the gravel cleaner a little. It is supposed to be 2 inches outside diameter. The pad, the way I put it on trims that down some. Will this mess up my base gains. I’ve been using it for 3 weeks. Also, do I have to be getting flaccid gains to get erect gains. My flaccid is small like 3 inches, mabey less.