Why are discus so expensive?
While Discus are not really hard to breed they do need much better care than many common aquarium fish. Many of the common fish you can just throw them in a pond in a tropical area, feed them and come back in 6 months with a net and scoop out hundreds of small fish. So they are super cheap to breed. Breeding discus requires more care, very good water condtions, less fish to the tank and the expensive bigger ones are probably a year or so old. They had to be kept in very good conditons and fed good food to get them to grow. All that makes them more expensive. Plus, people really like them, so shops can charge more, and people will pay.