Just to clarify, there's always a chance of species territorial aggression. All fish are individuals in character just as humans are. Statistically there has to be a jerk in the bunch eventually. It's good practice to make sure you're ready for undesirable situations. Be it disease or aggressive behavior. Having a QT tank ready to house angry, sick or battered fish is an easy way to make sure you're ready for whatever troubles may manifest.yeah thanks so much!