Trigger will go after any and all crustaceans since it is what they eat in the wild. My niger is a model citizen but I’ll still replace clean up crew regardless
I agree with the above posts as well. I did find that you can curb their desire to eat inverts a bit by keeping them fed. regardless, their teeth continuously grow and shells help keep them under control.
I dont think a bluethroat will seek out your cleanup crew as long as you feed him plenty. Triggers have a big appetite. I have a Clown, Sargassum, Blueline, Assasi and niger in my mixed reef tank and all they eat is the food I give them. They leave all cleanup crews alone and all the corals. As you can tell triggers have been my favorite fish for 30+ years and have had them in all tanks. Just feed them alot, if you under feed them they will look for other forms of food.