Salminus and it looks like franciscanus.
As a growout for sure. Need lot of space and current. The sticky in the characin section by chixclub has lot of info. If I remember right will be needing a 500g to get it fully grown with high current.
Dont keep any myself. But i'm sure some of the dorado keepers can chime in about the 200g. Not sure if it'll result in early death or not.
Dorados require a lot of room not only because of their rapid growth but also due to their constant motion. 200g is going to get small in a hurry.