what do you mean breeding them in a 50 gal tank? From my experience and my breeding pair of angels, they killed off the other angels in the tank when they choose to mate..Also, when I had them in a community tank, they wouldn't hurt the other fish in the tank but..the eggs wouldn't last over night..they would either eat them or I'm sure other fish ate them...very defensive fish lol
I keep them in their own 60 gal tall tank.
However,the storage containers for the fry might work out..I'm not sure..I always just used a 20 gal tank once they were free swimming.