translocation with hydrodynamics effects

I want to simulate polymer translocation throught a nanopore.I made a wall with a cylindrical pore in its center and i set this wall as a mambrane in middle of a box. I set the first bead of polymer (bead-spring chain) inside the pore. In order to take account into hydrodynamics effects on polymer translocation, i used fix srd command to make srd particles as a background solvent.Apparently srd paticles just do interact with the solute particles.So srd particles could not do interact with particles of wall and they passed from wall. But i want srd particles can do interact with wall’s particles by a repulsive potential in order to have an impermeable membrane.So i think i can use fix wall/srd command to solve this problem.
If it is possible for you ,please help me how i make a wall can do interact with both srd particles and polymer as the solute paticles simultaneously?

Fix wall/srd is an idealized flat wall. If you want to build
a wall of particles, then simply make it dense enough that
there are no holes, and SRD particles will bounce off
the wall particles just as they would bounce off solute