We studied Betta fish and their aggressive behavior in reaction to a perceived threat stimulus at two different distances. Betta fish have been known to display aggressive behaviors when in the presence of other fish and at their own reflection. We hypothesize that the Betta fish will display more aggressive behaviors when a mirror is present and at a closer proximity because a close mirror may replicate the experience of a more immediate threat. To test this, we placed mirrors at one or eight inches away from their tanks and observed. If the Bettas flared their fins and rubbed their faces against the side of the tank, we characterized their behavior as aggressive. We found that our hypothesis was incorrect and there was no signficant difference between aggression presentation at one or eight inches. Additionally, we compared aggressive behavior in Delta Tail Bettas and Veiltail Bettas. We hypothesized that there would be a difference in aggression between the two betta species. Our hypothesis was supported, and we found that Delta Tail Bettas were significantly more aggressive than Veiltail Bettas. For breeders and owners of novelty fish, knowing what stimlui results in aggressive behavior can be beneficial for preventing stress and choosing what species to breed and own. Furthermore, studies on aggression in bettas allows researchers to study how aggression relates to survival and mating, and how bettas compared to related species.