Most hawkfish are territorial towards conspecifics unless they come in as a pair (even in 500+g). Hawkfish and wrasses mix just fine together, but depending on the species you may want to introduce one first over the other. For example, introduce fairy wrasses before a flame or spotted hawkfish and introduce pixie or long nose hawkfishes if you get large wrasse spp. such as Gomphosus, Thalassoma, etc. I've pair long nose hawks' more reliably than other species.