Yea the active thing, is simply the pinstripe seems to be more dominant, and him laying ontop again is a "dominant" thing. ITs a very easy mistake for people to miss, when they are new, like i said if you CANT get a separate tank right away, even add 2 of everything for them to get away from eachother, and not fight over one resource (pin cant soak to naturally kill the mites so he'll be stressed) OR even split it with a piece of acrylic or plexiglass in the middle of tank (they are small enough they can each have a shoe boxed sized enclosure)