That is an odd stocking I will say that. Now im not an expert on this but I think you would have to keep the water conditions appropriate for the discus and the angels would have to adapt since they are more tollerent of not ideal conditions. Next would be aggression and feeding issues. The angels would outcompete the discus in both of these so you have to watch so your sure the discus are getting fed. Long term it could go eithed way. It could a great success or a complete flop. Im thinking 3 angels and 2 discus.