Discus are not great for community aquariums that's a fact. I'm sure there are many who would disagree but Keeping Discus only is the best way to keep then in safe, shape and healthy. I have seen Discus live with Oscars and other unbelievably aggressive fish but those are isolated and I can say "Lucky" cases. Even thought the Title say "Discus Tank mates" I want to point out few things why should Discus keep only with themselves.
- Discus is an Slow moving fish. They are not always quick about food so they might find it hard to fight for food with their other tank mates.
- Discus fish can be aggressive among themselves but they usually get bullied by other type of fish. They are not good at surviving under this kind of situations.
- Discus fish easly get diseases than other fish. So Those illnesses which might not hurm other fish a lot might effect badly for Discus fish. Specailly worm problems.
- Discus prefer clean water They don't like messed up or dirty water conditions. Its prefer hard to keep Aquarium water clean with most of other fish types.
- Discus get stressed quickly and easly.
- to grow fast Discus needs quality food which might eaten up by other fish who don't need this type of food to grow. Also you can feed young Discus upto 8 times a day which wont be great for most of other fish types.