<a href=showthread.php?s=&postid=8376616#post8376616 target=_blank>Originally posted</a> by mobert
In my experience, a pair of Clarkii and a pair of Oscellaris do not work in a 240 gallon with lots of rocks, and more than a dozen anemones at opposite sides of the tank with rock work arranged so that pairs don't have to look at each other. The Clarkii grabbed the Perc and shook it like it was trying to break the Perc's neck. Very aggressive behavior not otherwise seen. I don't know how else you can test the combination but my "common knowledge" comes from personal experience and from helping others who have tried mixing clowns on this forum. I was able to pull the Oscellaris out and put them in another tank but is that what you want to do? Fish get more aggressive as they get sexually mature. I don't think you can put more than a single pair of aggressive clowns in one tank.