I have a Niger trigger that I bought from a LFS that got him from a 1,000 gallon tank in a mall because he was killing his tank mates. I put him in with my 13" long puffer and some other fish and he was biting them, so I took him out and he's in a 45 gallon tank with my Giant Frogfish until I get someplace else to put him.
They do fine together, he's 10" or so and the Frogfish is 14" just about.