I have both the niger and blue throat in my tank and so far both have been model citizens
Have had 2 niger's and neither of them touched my cleaner shrimps. So i would say your shrimps are fairly safe.hmm, I have booked a Niger Trigger... cant decide if I should risk it or not, its not overly large at this stage however.. I obviously like my shrimps and hermits!
I had this conversation with Adriaan the other day about triggers as he is getting me a clown trigger, I was concerned about it destoying my tank but he told me that it would be o.k as he has a few clients with clown triggers in their setups with no problems at all.