it really depends on the trigger and his personality. They can be very agressive at times, and kinda have a jeckle/hyde personality. I have a clown trigger in with an assasi and a grouper and they do fine. But I did make sure to add the clown last. If u do get a clown trigger, make sure hes the last to go in, and a bit smaller than everyhting else. (But not too small, because when they are babies and small juvis they tend to be much less hardy than they are known for.)