ctaylor,
I said the discus keepers were like a cult as had friends through out the years who kept them, they were rather anal on their care and remember they used to get into arguments over aspects of discus care , lol .One still has them. I don't know how they are kept now but my friends were make food for them beefheart, worm ,etc combos .
In the 70s the only discus were the wild color but by think early to mid 80s , if not later a few colors began to appear in the hobby . The prices were insane , lol . The die off was absurd , We used to call them 'freshwater marine fish" because they were than harder than marine fish .
They were kept with angelfish back than because the theory was that they were found in same vicinity but later people realized that adult angels were too aggressive and think it turned out that angels were found in cooler water but of course same river.
They are very pretty and I do like the different type strains.