I just got a new tank that is probly around 20-30 gallons, would I be able to keep a discus or two in there with an angel fish or is that over stocking and would an angel and discus be a bad idea? Verry new to fish that aren't in the piranha family or type of betta. I've heard that discus are hard fish to keep and they are kinda on the expensive side so Im kinda scared to try them out, but I would love one so much.