[Madfish]

Like fishscale said discus do better in groups. I smallest amount of discus I would ever keep is 5 and in a 40gal that is really pushing it with just the discus. Plus if you dont want stunted discus you will have to do alot of water changes. With them only at 2in you should be doing 50-100% daily water changes. The best thing I can say is read up as much as you can about them before you even start to pick them out. And when you think you know what your doing stop and learn some more. But hey what do I know other than I have been keeping and breeding them for one or two or ten years but who keeps track of years anyways. As for plants alot of them will take the higher temps that you will be keeping discus at but there is alot of them that will melt too. But for your 40 I would see if the breeder has a breeding pair that would be alot better and juvies.