Adding More Discus to the Tank - 4 Blue Diamonds

The 5 Cobalt discus are doing fine, but it's time to add more, 9 discus should be a good number for this tank as they grow. I am hoping this helps spread out and diffuse the aggression as well as make the tank look a little more "complete". I think 9 looks good. I have some footage at the end just showing the tank at night. It is noteworthy that the discus seem to know it is night even though I left the lights on a little longer than usual today. I tried to get a night shot the previous night after the lights were off by gradually increasing the light from dark to light, and the discus were all sleeping! I had never seen that before. There was no use in trying to get any footage, it was as if all the fish were deactivated for the evening. Their eyes even looked different.