I have ... and to me thats not a viable option.
If the main goal of the tank is to keeping shrimp, then not adding something that is going to snack on adults is the best option. Especially because chances are that offspring are also on the menu and you then lose that source keeping the colony viable...They are welcome to eat the shrimp ... Just don't want them eating them ALLLL
I do not just want to add something. I am just more into lowtech low maintenance tanks.