Another thought. I have a similar net, similar mesh, and I can't keep the bottom on the ground. Although it isn't likely that RES will go under the bottom edge, I know some of my fish (perch, goldfish, LCS) do have no problem scooting in the mud and shimmying in and out of the net.
I bought some fast setting concrete in a bag and mixed it a bit soupy and scooped up the wet concrete into plastic cups. I then put a 6" piece of wire in each one before they set. They set in about an hour and are easy to shell out of the cups later. I used thes to add weights to the existing weights. Even with my added weights when pulling the nets on an uneven bottom while seining, the fish find little uneven spots on the bottom and shoot out.
You might think about weighting the bottom like this, or better yet, getting some cheap metal tent stakes and staking the bottom here and there to keep things in that you want in.
In this picture I have 2 nets tied together to get the desired length. I added cement weights in between just about every existing factory weight. The factory weights were terribly inadequate. A shame that they even called them weights!
