Hi Turock, Discus do that,they chase each other around,I was kind of Surprised by that to.If one Fish is getting injured to the point that the Fish might be killed,you should move that Fish to another Tank.I recently started a 47 Gallon Cube Aquarium and put a Piece of Driftwood Right in the center,That way they can chase each other around the Piece of Driftwood.It's only worked a little bit,I still see Fish with scales missing from there sides, from being rammed into.But there Healthy enough to endure it.How do you like your Discus from Mac's Discus?I was thinking of ordering from them.