Planted Tank Guru
Join Date: Jul 2010
Location: British Columbia, Canada
Roselines - Denison's Barb - are beautiful fish, and while possibly some may have successfully kept them with discus, I would rather doubt they would be compatible tank-mates for discus.
They are very active, fast-moving fish that can become quite aggressive over food, and even though I haven't personally kept them with discus, I believe they would tend to stress discus, intimidate them, and out-compete them for food.
They also prefer cooler temps - 76-79 and discus will not tolerate, over the long term, temp under approx 82 F and still remain healthy & thriving.