how to define interation between srd particles and big particles

Hi,
If it’s possible for you,please see my input and data files i attached. my system composed of a bead-spring chain , a wall and SRD fluid particles
I set diameters of polymer’s beads = 1.0 , diameters of wall’s particles = 2.0 and diameters of SRD fluid particles = 0.0 and i set the characteristic length scale for the SRD fluid= hgrid=0.25=1/4 diameters of polymers’s bead
I set particles of wall and chain in big group as big particles in fix srd command.
I made configuration of my system with packmol. At first i set small particles with diameter=0.0 as background fluid in left side of wall.
I need to set repulsive interaction between small(srd)particles in order to srd particles can not move thru wall So i use pair_style cut/lj
But unfortunately i saw srd particles during performance of input are moving thru wall and can go to other side of wall and this is not good because the wall should be Impermeable against srd particles as background fluid.
also performance of input is stopped with an error as follows:
ERROR: Lost atoms: original 5818 current 5816
Please see and check my input and say me what is my mistake
Thank in advance for your help
samira

in.fwp (1.23 KB)

data.fwp (203 KB)

sorry, I don't have time to debug other people's input scripts.
I suggest you start with the SRD examples provide in examples/srd
and work your way up to your system.

Steve