I have a 150g (72X18X29) tank, I currently have 3 severums and 4 angles and about 75 tetras in the tank. I am thinking of switching every thing over to my 230 would it possible to have all of the above mentioned fish in the same tank?
I wouldn't keep Severums with discus, they don't do well in the higher heat, and they tend to be aggresive towards discus. I also wouldn't keep rays, although I know there are folks that it works for, I've also seen pics of a half eaten discus from a ray tank..........Discus and angels do ok together although the angels will feed more aggresively and you'll need to watch that the discus get enough food.......
I wanted to do the Discus/Stingray set up too . . . after spending hours scavenging for practical experience on it I decided not to do it . . . after adding things up seems about 75% of the time the rays and discus peacefully coexist, but there were enough instances of the discus getting killed to scare me out of it . . .especially if you're getting expensive Discus morphs from a breeder and not the normal ones most lfs have
Also, Discus and Angelfish can work well together, but Angelfish are notorious for carrying parasites that can wreak havoc on Discus so make sure they are all in exceptional health before mixing