Yes killi's can be quite aggressive, just a heads up. I once had a pair of aphysemion gardneri in a tank with some pseudomugil furcatas. I did this because my gf was changing up tanks, and needed a place for her killi's. In one night the killis managed to bite the tailfins of all my furcatas straight off. (They grew back fcourse). But these fish are definitely hunters!
Sent per three-eyed raven..