No, I don't think they will bother eachother...I had an orange one with my blue and they left eachother alone. The orange died when someone decided to play with my algae scraper and hit it off the top glass really hard injuring it. I know that there is nothing like the color on the blues, they really stand out...you can see them from clear across the room. Mine is one of the first things people notice, especially since it is always out in the open.