Plus if done by someone with experience you can treat only the open water near where they are with low dose and not near shore where the BG , LMB etc are. Shad can also be driven (boats and noise) to one end and treated there.

Gill nets work well also in open water. Try to take out the big GShad and the LMB can work on small ones but there have to be enough LMB of the correct size to do that.