My 2 cories don't seem to bother the shrimp at all unless I put in some bottom feeder pellets, then they only come around and shove the shrimp out of their way. Obviously the CPD's aren't eating too many of the shrimplets because my colony is growing.
I think I will leave everything alone. I apparently have a good balance since plants and fish all seem to be healthy and the shrimp colony is growing but not exploding in population.
Thank you all for your input!