hi dan,welcome to SD
if you could set up a 55gl bare bottom tank for your new discus that would be great to power feed them and lots of water changes.
vary thier diet with different kinds of foods like frozen foods or you could make your own,its cheaper in the long run.
i dont know what kind of light and substrate you have so
at the same time you could invest time and money to set up 150 into a planted tank ,like substrate light and plants.
stick with low light plants if this is your first time.