Maybe you can start out by importing fish and let your breeding business run parallell in smaller scale while you get going?
Here in Sweden we have some of the highest costs and taxes in the world and the aquarium hobby is not very big. Yet I know of one pure discus facility (combined import and breeding) and one with discus along with several other fish. As far as I know this is their full time work. But obviously you would have to be driven by interest rather than by expecting huge profit.